아리엘 대학과 ISF 개별 연구 보조금에서 시작 그랜트 (1914/15) AMS를 기꺼이 인정 된다.

1입니다. Enolonium 종 준비
주의: 프로토콜을 수행 하기 전에 모든 시 약 및 용 매에 대 한 MSDS를 참조.
참고: 상용 소스 로부터 받은 모든 새로운 시 약 사용 되었다. 붕 소 trifluoride etherate를 저장 하는 경우 사용 하기 전에 그것을 증 류.
<ol><li>둥근 바닥된 플라스 크는 심장 및 자석 마그네틱 감동에 대 한 장비 건조, 추가 Koser의 시 약 (1.5 equiv.) 질소 또는 아르곤 플라스 크를 플러시.</li>
	<li>0.234 mol/L 공식 농도의 현 탁 액을 주고 건조 dichloromethane을 추가 합니다.</li>
	<li>쿨 드라이 아이스/아세톤 목욕 또는 차가운 손가락 악기/아세톤 목욕을 사용 하 여-78 ° C에 서 스 펜 션.</li>
	<li>깔끔한 BF3OEt2 추가 (1.5 equiv.) 천천히.</li>
	<li>노란 솔루션의 형성까지 실내 온도에 다른 유형의 혼합물을 따뜻한. 일반적으로,이 5 분 이내 발생합니다.</li>
	<li>-78 ° c 솔루션 쿨</li>
	<li>냉각된 솔루션에 추가 trimethylsilyl enolether (1 equiv., 0.313 mol/L)에서 건조 dichloromethane dropwise (규모)에 따라 2-10 분 이상. Silyl enol 에테르의 추가 완료 한 후 enolonium 종 형성 완료 됩니다. 참고: enolonium 종의 솔루션 수 있습니다 남아 있을 적어도 30 분 동안-78 ° C에 수확량에 더 악화. Enolonium 종 보고 NMR 연구6에 표시 된 대로이 시간 동안 안정적입니다.</li>
</ol>2입니다. Enolonium 종의 기능화
<ol><li>염화 염화 물 음이온과
	<ol>
<li>Enolonium 종 준비 솔루션, 염화 비닐 벤 질 디 메 틸 decylammonium 추가 (2.0 equiv., 1.25 mol/L) 건조 dichloromethane 드롭 현명한 방식에서에. -55 ° c 온도 유지 되도록이 솔루션에 추가 0.5-2 mmol 규모 또한 5 분 이상 만족입니다.</li>
		<li>5 분 동안-78 ° C에서 반응 혼합물을 남겨 주세요.</li>
		<li>냉각 목욕을 제거 하 고 실내 온도 도달 하는 반응 혼합물을 허용.</li>
		<li>20 분 동안 실 온에서 반응을 남겨 주세요.</li>
		<li>반응 혼합물 (enolonium 종의 준비에 사용 되는 dichloromethane의 절반 볼륨)에 물을 추가 합니다.</li>
		<li>Dichloromethane을 몇 번이 고 압축을 풉니다. 일반적으로 2-3 시간 반응 볼륨을 사용 하 여 0.5-2 각 추출에 mmol 작은 규모.</li>
		<li>결합 된 유기 레이어 두 번 소금물을 씻어. 일반적으로, 소금물의 동일한 볼륨을 사용 하 여 결합된 반응 볼륨으로.</li>
		<li>30 분 동안 무수 황산 나트륨으로 건조.</li>
		<li>(예를 들어, 통해 Celite 플러그) 나트륨 황산 염을 필터링 합니다.</li>
		<li>감압 및 40 ° c.에서 회전 증발 기에 용 매를 제거</li>
		<li>칼럼 크로마토그래피는 용 매 제거 후 순수 해당 α-azido 케 톤을 감당할 헥 산 및 에틸 아세테이트 eluents를 사용 하 여 실리 카 젤에 의해 원유 제품을 정화. 참고: trimethylsilyl enolate의 2 mmol 0.5 m m o l의 비늘에 2 cm 직경 15 cm의 높이 (길이)에 표준 실리 카 젤 60을 사용 하 여 유리 열에 열 크로마토그래피 수행 합니다. 볼륨 다른 비늘에 대 한 다양 한 필요 합니다.</li>
	</ol></li>
	<li>TMS-아 지 드와 Azidation 주의: 유기 azides 일반적으로 폭발성 고 주의 처리 및 제품을 준비 한다. TMS-아 지 드 독성이 있다. 사용 하기 전에 MSDS를 참조 하십시오.<ol>
<li>Enolonium 종-78 ° C에서의 준비 된 솔루션에 추가 하는 깔끔한 azidotrimethylsilane (2.5 equiv.) dropwise 방식에서. 되도록 온도가-55 ° c에이 솔루션 추가 0.5-2 mmol 규모, 추가 2-3 분 이상 만족 이다.</li>
		<li>-78 ° c.에 15 분 동안 반응 혼합물을 저 어</li>
		<li>-55 ° C에 반응 혼합물이 열 하 고 2 ~ 3 h에 대 한이 온도에 둡니다.</li>
		<li>반응 혼합물 (enolonium 종의 준비에 사용 되는 dichloromethane의 절반 볼륨)에 물을 추가 합니다.</li>
		<li>Dichloromethane을 몇 번이 고 압축을 풉니다. 일반적으로 2-3 시간 반응 볼륨을 사용 하 여 0.5-2 각 추출에 mmol 작은 규모.</li>
		<li>결합 된 유기 레이어 두 번 소금물을 씻어. 일반적으로, 소금물의 동일한 볼륨을 사용 하 여 결합된 반응 볼륨으로.</li>
		<li>건조 30 분 무수 황산으로 추출.</li>
		<li>나트륨 황산 염을 필터링 합니다.</li>
		<li>감압 및 40 ° c.에서 회전 증발 기에 용 매를 제거</li>
		<li>칼럼 크로마토그래피는 용 매 제거 후 순수 해당 α-azido 케 톤을 감당할 헥 산 및 에틸 아세테이트 eluents를 사용 하 여 실리 카 젤에 의해 원유 제품을 정화.</li>
	</ol></li>
	<li>Azoles와 반응
	<ol>
<li>Enolonium 종-78 ° C에서의 준비 된 솔루션에 추가할 azole (4 ~ 5 equiv., 1 mol/L)에 dropwise 패션 dichloromethane의 5 mL에 용 해. 0.5-2 mmol 규모 또한 5 분 이상 만족입니다. 참고: tetrazoles 같은 가난 하 게 녹는 azoles 경우 dichloromethane 대신 0.5 mol/L의 농도에서 이기를 사용 합니다. 되도록 온도가-55 ° c에이 솔루션 추가</li>
		<li>-78 ° c.에 15 분 동안 반응 혼합물을 저 어</li>
		<li>-55 ° C에 반응 혼합물이 열 하 고 4 ~ 8 h에 대 한이 온도에 둡니다.</li>
		<li>반응 혼합물 (enolonium 종의 준비에 사용 된 유기 용 제의 절반 볼륨)에 물을 추가 합니다.</li>
		<li>Dichloromethane을 몇 번이 고 압축을 풉니다. 일반적으로 2-3 시간 반응 볼륨을 사용 하 여 0.5-2 각 추출에 mmol 작은 규모.</li>
		<li>결합 된 유기 레이어 두 번 소금물을 씻어. 일반적으로, 소금물의 동일한 볼륨을 사용 하 여 결합된 반응 볼륨으로.</li>
		<li>건조 30 분 무수 황산으로 추출.</li>
		<li>나트륨 황산 염을 필터링 합니다.</li>
		<li>감압 및 40 ° c.에서 회전 증발 기에 용 매를 제거</li>
		<li>칼럼 크로마토그래피는 용 매 제거 후 순수 해당 α azole 케 톤을 감당할 헥 산 및 에틸 아세테이트 eluents를 사용 하 여 실리 카 젤에 의해 원유 제품을 정화.</li>
	</ol></li>
	<li>Allylation, crotylation, cinnamylation, 및 prenylation 사용 하 여 알릴 실
	<ol>
<li>추가 하는 깔끔한 알릴-, crotyl, cinnamyl, 또는 prenyl trimethylsilane (2 equiv.)-78 ° c.에 천천히 되도록 온도가-55 ° c에이 솔루션 추가 0.5-2 mmol 규모, 추가 2-3 분 이상 만족 이다.</li>
		<li>-78 ° c.에서 10 분에 대 한 반응 혼합물을 저 어</li>
		<li>천천히 냉각 목욕을 제거 하 여 실내 온도를 따뜻하게 반응 혼합물을 허용 한다. 20 분 동안 실 온에서 반응을 남겨 주세요.</li>
		<li>반응 혼합물 (enolonium 종의 준비에 사용 되는 dichloromethane의 절반 볼륨)에 물을 추가 합니다.</li>
		<li>Dichloromethane을 몇 번이 고 압축을 풉니다. 일반적으로 2-3 시간 반응 볼륨을 사용 하 여 0.5-2 각 추출에 mmol 작은 규모.</li>
		<li>결합 된 유기 레이어 두 번 소금물을 씻어. 일반적으로, 소금물의 동일한 볼륨을 사용 하 여 결합된 반응 볼륨으로.</li>
		<li>건조 30 분 무수 황산으로 추출.</li>
		<li>나트륨 황산 염을 필터링 합니다.</li>
		<li>감압 및 40 ° c.에서 회전 증발 기에 용 매를 제거</li>
		<li>칼럼 크로마토그래피는 용 매 제거 후 순수 해당 α-알릴 제품을 감당할 헥 산 및 에틸 아세테이트 eluents를 사용 하 여 실리 카 젤에 의해 원유 제품을 정화.</li>
	</ol></li>
	<li>Arylation 참고: arylation, 사용 3 해당 BF3OEt2 의 enolonium 종의 준비 하는 동안 주요 측면으로는 enolonium의 tosylation를 피하기 위하여. 일반적으로, 향기로운 기판만 1.6 상응이 필요 합니다. 그러나, 경우 아로마 기판은 pyrane, thiophene, 또는 pyrrole, 최상의 결과 향기로운 기판의 5 항목을 사용 하 여 달성 된다.<ol>
<li>준비 된 enolonium의 솔루션 종 건조 dichloromethane에 향기로운 기판의 솔루션 추가 (1.6 equiv., 0.5 mol/L) dropwise 방식에서. 되도록 온도가-55 ° c에이 솔루션 추가 0.5-2 mmol 규모, 추가 5-10 분 이상 만족 이다.</li>
		<li>향기로운 기판의 추가 완료 되 면-55 ° C에 혼합물의 온도 증가 하 고 20 분 동안이 온도에 혼합물을 두고.</li>
		<li>반응 혼합물 (enolonium 종의 준비에 사용 되는 dichloromethane의 절반 볼륨)에 물을 추가 합니다.</li>
		<li>Dichloromethane을 몇 번이 고 압축을 풉니다. 일반적으로 2-3 시간 반응 볼륨을 사용 하 여 0.5-2 각 추출에 mmol 작은 규모.</li>
		<li>결합 된 유기 레이어 두 번 소금물을 씻어. 일반적으로, 소금물의 동일한 볼륨을 사용 하 여 결합된 반응 볼륨으로.</li>
		<li>건조 30 분 무수 황산으로 추출.</li>
		<li>나트륨 황산 염을 필터링 합니다.</li>
		<li>감압 및 40 ° c.에서 회전 증발 기에 용 매를 제거</li>
		<li>칼럼 크로마토그래피는 용 매 제거 후 순수 해당 α-arylated 케 톤을 감당할 헥 산 및 에틸 아세테이트 eluents를 사용 하 여 실리 카 젤에 의해 원유 제품을 정화.</li>
	</ol></li>
</ol>

<ol>
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V., Waser, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Azidation+of+&#946;-keto+esters+and+silyl+enol+ethers+with+a+benziodoxole+reagent.">Azidation of &#946;-keto esters and silyl enol ethers with a benziodoxole reagent.</a> Organic Letters. 15 (13), 3246-3249 (2013).</li><li>More, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=&#945;-N-Heteroarylation+and+&#945;-azidation+of+ketones+via+enolonium+species.">&#945;-N-Heteroarylation and &#945;-azidation of ketones via enolonium species.</a> Journal of Organic Chemistry. 83, 2442-2447 (2018).</li><li>Xie, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold-catalyzed+hydration+of+haloalkynes+to+&#945;-halomethyl+ketones.">Gold-catalyzed hydration of haloalkynes to &#945;-halomethyl ketones.</a> Journal of Organic Chemistry. 78 (18), 9190-9195 (2013).</li><li>Patonay, T., Juh&#225;sz-T&#243;th, &. #. 2. 0. 1. ;., B&#233;nyei, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Base-induced+coupling+of+&#945;-azido+ketones+with+aldehydes+&#8722;+An+easy+and+efficient+route+to+trifunctionalized+synthons+2-azido-3-hydroxy+ketones,+2-acylaziridines,+and+2-acylspiroaziridines.">Base-induced coupling of &#945;-azido ketones with aldehydes &#8722; An easy and efficient route to trifunctionalized synthons 2-azido-3-hydroxy ketones, 2-acylaziridines, and 2-acylspiroaziridines.</a> European Journal of Organic Chemistry. 2002 (2), 285-295 (2002).</li><li>Li, C., Breit, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rhodium-catalyzed+chemo-+and+regioselective+decarboxylative+addition+of+&#946;-ketoacids+to+allenes:+Efficient+construction+of+tertiary+and+quaternary+carbon+Centers.">Rhodium-catalyzed chemo- and regioselective decarboxylative addition of &#946;-ketoacids to allenes: Efficient construction of tertiary and quaternary carbon Centers.</a> Journal of the American Chemical Society. 136 (3), 862-865 (2014).</li></ol>

공개 하는 것이 없다.

TMS enolates에서 enolonium의 성공적인 준비는 여러 가지 요인에 따라 달라 집니다. 준비 단계에서 주요 측 반응은 TMS enolate의 분자 형성된 enolonium의 분자의 반응에 의해 시작 물자의 호모 커플링 이다. 따라서, 반응 조건의 요구 이합체 화의 속도 기준으로 추가 TMS enolate와 루이스 산 활성화 hypervalent 요오드 시 약의 빠른 반응 함으로써이 이합체 화를 방지 하는. 이 프로토콜에 활성화 하 고 solubilizing Kos...

Enolates 클래식 탄소 nucleophiles 유기 화학에서 그리고 중 가장 널리 사용 되는. Electrophilic enolonium 종 만들려고 enolates의 Umpolung는 귀중 한 대체 방법으로 α-기능성된 ketones을 생산으로 소설 반응 클래식 enolate 화학을 통해 불가능을 가능 하 게 하 수 있습니다. Enolonium 종 hypervalent 요오드 시 약을 포함 하는 특정 반응에 많은 반응에서 중간체도 제안 되었습니다. 이러한 반응에는 α-halogenation, 산소, 그리고 amination1 뿐만 아니라 다른 반응2,3,,45포함 됩니다.
그러나, 이러한 반응의 범위는 항상 반응 enolonium 종의 과도 특성에 의해 제한 되었다. 이 transiency 필요 어떤 nucleophile 강하게 산화 hypervalent 요오드 시 약으로 생성 enolates의 반응 동안 반응 혼합물에 있어야 합니다. 따라서, 어떤 nucleophile 전자 부유한 향기로운 화합물 (heterocycles) 및 알 켄와 같은 산화 하는 경향이 사용할 수 없습니다.
작년에 우리 뒤에 두 번째 단계에서 nucleophile의 추가 1 단계에서 개별 중급으로 enolonium 종 형성은 조건 개발 하 여 이러한 한계를 극복 했다. 이 프로토콜 허용 기능화 염소6, 등의 고전 형식 뿐만 아니라 산화 탄소 nucleophiles allylsilanes6,8, enolates1,6,등의 사용 7, 그리고 전자 부유한 향기로운 화합물9, C-C 유대 형성의 결과. Allylation 메서드는 의무가 제 사기 및 3 차 센터의 형성. 케 톤 arylation 방법의 향기로운 감독 그룹9에 대 한 필요 없이 복합 형식 C H 기능화를 구성합니다. 최근에, 우리는 뿐만 아니라11로 azoles 및 azides10 의 추가 보고 있다. 프로토콜의 상세한 프레 젠 테이 션 합성 유기 화학자의 나날 도구 상자에 이러한 방법의 소개에 지원 예정입니다.

<table>
	<tbody>
		<tr>
			<td>Chlorotrimethylsilane, 98+%</td>
			<td>Alfa Aesar</td>
			<td>A13651</td>
			<td>TMS-Cl</td>
		</tr>
		<tr>
			<td>Boron trifluoride diethyl etherate, 98+%</td>
			<td>Alfa Aesar</td>
			<td>A15275</td>
			<td>BF3*Et2O</td>
		</tr>
		<tr>
			<td>2-Methylindole, 98+%</td>
			<td>Alfa Aesar</td>
			<td>A10764</td>
			<td>2-Me-indole</td>
		</tr>
		<tr>
			<td>Hydroxy(tosyloxy) iodobenzene, 97%</td>
			<td>Alfa Aesar</td>
			<td>L15701</td>
			<td>Koser&#39;s reagent</td>
		</tr>
		<tr>
			<td>Acetophenone, &#62;98%</td>
			<td>Merck</td>
			<td>800028</td>
			<td></td>
		</tr>
		<tr>
			<td>n-Butyllithium solution 1.6M in hexanes</td>
			<td>Aldrich</td>
			<td>186171</td>
			<td>nBuLi</td>
		</tr>
		<tr>
			<td>BIS(ISOPROPYL)AMINE</td>
			<td>Apollo</td>
			<td>OR1090</td>
			<td>DIPA</td>
		</tr>
		<tr>
			<td>Trimethylsilyl azide, 94%</td>
			<td>Alfa Aesar</td>
			<td>L00173</td>
			<td>TMS-N3</td>
		</tr>
	</tbody>
</table>

a two-step protocol for umpolung functionalization of ketones via enolonium species

Α-기능화 hypervalent 요오드 시 약에 의해 enolates의 umpolung 통해 ketones의 합성 유기 화학에서 중요 한 개념 이다. 최근에, 우리는 케 톤 enolate umpolung 수돗물, azidation, 및 amination azoles를 사용 하 여 메서드의 개발 활성화를 위한 2 단계 전략을 개발 했습니다. 또한, C C 본드-형성 arylation와 allylation 반응 개발 했습니다. 이러한 방법의 중심에는 반응 nucleophile의 추가 이전 중간과 높은 반응 enolonium 종의 준비 합니다. 이 전략은 따라서 준비 및 고전적인 합성 화학 금속 enolates의 사용의 연상 이다. 이 전략 nucleophiles 것 그렇지 않으면 호환 되지 않을 수 강하게 산화 hypervalent 요오드 시 약의 사용을 허용 한다. 이 문서에서 우리는 염소, azidation, N-heteroarylation, arylation, 및 allylation에 대 한 자세한 프로토콜 제시. 제품 모티브 medicinally 활성 제품에 포함 됩니다. 이 기사 크게 이러한 메서드를 사용 하 여 다른 사람을 도움이 됩니다.

대표 실적, 프로토콜, 다음 그림 1 에 그리고 토론 섹션에서 설명 됩니다. 특히, 다른 ketones의 아주 큰 범위 사용할 수 있습니다 성공적으로 반응에서에 대해서 제품 좋은 수익률 azidation11볼 수 있습니다. 소개 azoles ketones의 α-위치에 대 한 반응의 범위 heterocycles 포함 된 일반적인 모노 주기적와 bicyclic 질소의 대부분 포함. Allylation 절?...

Watch this Scientific Journal Video about A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species at JoVE.com

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

Enolonium 종 케 톤 enolates의 umpolung와 α-위치에 nucleophile의 추가 대 한 2 단계 한 냄비 프로토콜 설명 되어 있습니다. Nucleophiles 염화 물, 아 지 드, azoles, 알릴-실, 그리고 향기로운 화합물 포함.

Enolonium 종 통해 Ketones의 Umpolung 기능화에 대 한 2 단계 프로토콜

&#945;-Functionalization of ketones via umpolung of enolates by hypervalent iodine reagents is an important concept in synthetic organic chemistry. ...

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Aldehydes and Ketones

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9.9K 조회수.  Ariel University. Enolonium 종 케 톤 enolates의 umpolung와 α-위치에 nucleophile의 추가 대 한 2 단계 한 냄비 프로토콜 설명 되어 있습니다. Nucleophiles 염화 물, 아 지 드, azoles, 알릴-실, 그리고 향기로운 화합물 포함.

비디오: A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides (CHIPS)

The direct functionalization of C-H bonds is an important and long standing goal in organic chemistry. Such transformations can be very powerful in order to streamline synthesis by saving steps, time and material compared to conventional methods that require the introduction and removal of activating or directing groups. Therefore, the functionalization of C-H bonds is also attractive for green chemistry. Under oxidative conditions, two C-H bonds or one C-H and one heteroatom-H bond can be transformed to C-C and C-heteroatom bonds, respectively. Often these oxidative coupling reactions require synthetic oxidants, expensive catalysts or high temperatures. Here, we describe a two-step procedure to functionalize indole derivatives, more specifically tetrahydrocarbazoles, by C-H amination using only elemental oxygen as oxidant. The reaction uses the principle of C-H functionalization via Intermediate PeroxideS (CHIPS). In the first step, a hydroperoxide is generated oxidatively using visible light, a photosensitizer and elemental oxygen. In the second step, the N-nucleophile, an aniline, is introduced by Br&#248;nsted-acid catalyzed activation of the hydroperoxide leaving group. The products of the first and second step often precipitate and can be conveniently filtered off. The synthesis of a biologically active compound is shown.

Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides CHIPS

A two-step procedure for the synthesis of pharmaceutically active indole-derivatives by C-H functionalization with anilines is described, using photo- and Br&#248;nsted acid catalysis.

중간 과산화물을 통해 광화학 및 산 - 촉매 CH 기능화에 의한 항 바이러스 Tetrahydrocarbazole 유도체의 합성 (CHIPS)

The direct functionalization of C-H bonds is an important and long standing goal in organic chemistry. Such transformations can be very powerful in order ...

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A Protocol for the Production of Gliadin-cyanoacrylate Nanoparticles for Hydrophilic Coating

This article presents a protocol for the production of protein-based nanoparticles that changes the hydrophobic surface to hydrophilic by a simple spray coating. These nanoparticles are produced by the polymerization reaction of alkyl cyanoacrylate on the surface of cereal protein (gliadin) molecules. Alkyl cyanoacrylate is a monomer that instantly polymerizes at RT when it is applied to the surface of materials. Its polymerization reaction is initiated by the trace amounts of weakly basic or nucleophilic species on the surface, including moisture. Once polymerized, the polymerized alkyl cyanoacrylates show a strong affinity with the object materials because nitrile groups are in the backbone of poly (alkyl cyanoacrylate). Proteins also work as initiator for this polymerization because they contain amine groups that can initiate the polymerization of cyanoacrylate. If aggregated protein is used as an initiator, protein aggregate is surrounded by the hydrophobic poly(alkyl cyanoacrylate) chains after the polymerization reaction of alkyl cyanoacrylate. By controlling the experimental condition, particles in the nanometer range are produced. The produced nanoparticles readily adsorb to the surface of most materials including glass, metals, plastics, wood, leather, and fabrics. When the surface of a material is sprayed with the produced nanoparticle suspension and rinsed with water, the micellar structure of nanoparticle changes its conformation, and the hydrophilic proteins are exposed to the air. As a result, the nanoparticle-coated surface changes to hydrophilic.

This article presents a protocol for the production of protein-based nanoparticles that changes the hydrophobic surface to hydrophilic. The produced nanoparticle is an assembly of gliadin-cyanoacrylate diblock copolymers. Spray coating with the produced nanoparticle changes the surface of target material to a hydrophilic surface.

친수성 코팅 글 리아 딘 - 시아 노 아크릴 레이트 나노 입자의 생산을위한 프로토콜

This article presents a protocol for the production of protein-based nanoparticles that changes the hydrophobic surface to hydrophilic by a simple spray ...

Rapid High-throughput Species Identification of Botanical Material Using Direct Analysis in Real Time High Resolution Mass Spectrometry

We demonstrate that direct analysis in real time-high resolution mass spectrometry can be used to produce mass spectral profiles of botanical material, and that these chemical fingerprints can be used for plant species identification. The mass spectral data can be acquired rapidly and in a high throughput manner without the need for sample extraction, derivatization or pH adjustment steps. The use of this technique bypasses challenges presented by more conventional techniques including lengthy chromatography analysis times and resource intensive methods. The high throughput capabilities of the direct analysis in real time-high resolution mass spectrometry protocol, coupled with multivariate statistical analysis processing of the data, provide not only class characterization of plants, but also yield species and varietal information. Here, the technique is demonstrated with two psychoactive plant products, Mitragyna speciosa (Kratom) and Datura (Jimsonweed), which were subjected to direct analysis in real time-high resolution mass spectrometry followed by statistical analysis processing of the mass spectral data. The application of these tools in tandem enabled the plant materials to be rapidly identified at the level of variety and species.

A method for species identification of botanical material by direct analysis in real time-high resolution mass spectrometry and multivariate statistical analysis is presented.

실시간 고해상도 질량 분석에 직접 분석을 사용하여 식물 소재의 신속한 높은 처리량 종 확인

We demonstrate that direct analysis in real time-high resolution mass spectrometry can be used to produce mass spectral profiles of botanical material, ...

A Protocol for Safe Lithiation Reactions Using Organolithium Reagents

Organolithium reagents are powerful tools in the synthetic chemist&#39;s toolbox. However, the extreme pyrophoric nature of the most reactive reagents warrants proper technique, thorough training, and proper personal protective equipment. To aid in the training of researchers using organolithium reagents, a thorough, step-by-step protocol for the safe and effective use of tert-butyllithium on an inert gas line or within a glovebox is described. As a model reaction, preparation of lithium tert-butyl amide by the reaction of tert-butyl amine with one equivalent of tert-butyl lithium is presented.

The safe and proper use of organolithium reagents is described.

유기 리튬 시약을 사용하여 안전 리튬 화의 반응을위한 프로토콜

Organolithium reagents are powerful tools in the synthetic chemist&#39;s toolbox. However, the extreme pyrophoric nature of the most reactive reagents ...

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

Solid-phase synthesis has been used to obtain canonical and modified polymers of nucleic acids, specifically of DNA or RNA, which has made it a popular methodology for applications in various fields and for different research purposes. The procedure described herein focuses on the synthesis, purification, and characterization of dodecamers of RNA 5&#39;-[CUA CGG AAU CAU]-3&#39; containing zero, one, or two modifications located at the C2&#39;-O-position. The probes are based on 2-thiophenylmethyl groups, incorporated into RNA nucleotides via standard organic synthesis and introduced into the corresponding oligonucleotides via their respective phosphoramidites. This report makes use of phosphoramidite chemistry via the four canonical nucleobases (Uridine (U), Cytosine (C), Guanosine (G), Adenosine (A)), as well as 2-thiophenylmethyl functionalized nucleotides modified at the 2&#39;-O-position; however, the methodology is amenable for a large variety of modifications that have been developed over the years. The oligonucleotides were synthesized on a controlled-pore glass (CPG) support followed by cleavage from the resin and deprotection under standard conditions, i.e., a mixture of ammonia and methylamine (AMA) followed by hydrogen fluoride/triethylamine/N-methylpyrrolidinone. The corresponding oligonucleotides were purified via polyacrylamide electrophoresis (20% denaturing) followed by elution, desalting, and isolation via reversed-phase chromatography (Sep-pak, C18-column). Quantification and structural parameters were assessed via ultraviolet-visible (UV-vis) and circular dichroism (CD) photometric analysis, respectively. This report aims to serve as a resource and guide for beginner and expert researchers interested in embarking in this field. It is expected to serve as a work-in-progress as new technologies and methodologies are developed. The description of the methodologies and techniques within this document correspond to a DNA/RNA synthesizer (refurbished and purchased in 2013) that uses phosphoramidite chemistry.

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

This article provides a detailed procedure on the solid-phase synthesis, purification, and characterization of dodecamers of RNA modified at the C2&#39;-O-position. UV-vis and circular dichroism photometric analyses are used to quantify and characterize structural aspects, i.e., single-strands or double-strands.

2&#39;- 포스 핀 올리고 뉴클레오타이드를 함유하는 올리고머의 고상 합성을위한 프로토콜<em&gt; O</em&gt; 원형 이색 성을 통한 - 티오 페닐 메틸 변형 및 특성 분석

Solid-phase synthesis has been used to obtain canonical and modified polymers of nucleic acids, specifically of DNA or RNA, which has made it a popular ...

Fabrication and Testing of Catalytic Aerogels Prepared Via Rapid Supercritical Extraction

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three preparation methods are described: (a) the incorporation of metal salts into silica or alumina wet gels using an impregnation method; (b) the incorporation of metal salts into alumina wet gels using a co-precursor method; and (c) the addition of metal nanoparticles directly into a silica aerogel precursor mixture. The methods utilize a hydraulic hot press, which allows for rapid (&#60;6 h) supercritical extraction and results in aerogels of low density (0.10 g/mL) and high surface area (200-800 m2/g). While the work presented here focuses on the use of copper salts and copper nanoparticles, the approach can be implemented using other metal salts and nanoparticles. A protocol for testing the three-way catalytic ability of these aerogels for automotive pollution mitigation is also presented. This technique uses custom-built equipment, the Union Catalytic Testbed (UCAT), in which a simulated exhaust mixture is passed over an aerogel sample at a controlled temperature and flow rate. The system is capable of measuring the ability of the catalytic aerogels, under both oxidizing and reducing conditions, to convert CO, NO and unburned hydrocarbons (HCs) to less harmful species (CO2, H2O and N2). Example catalytic results are presented for the aerogels described.

Here we present protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms. Methods for preparing materials using copper salts and copper-containing nanoparticles are featured. Catalytic testing protocols demonstrate the effectiveness of these aerogels for three-way catalysis applications.

제조 및 급속 한 초 임계 추출 통해 준비 촉매 Aerogels의 테스트

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three ...

The MPLEx Protocol for Multi-omic Analyses of Soil Samples

Mass spectrometry (MS)-based integrated metaproteomic, metabolomic, and lipidomic (multi-omic) studies are transforming our ability to understand and characterize microbial communities in environmental and biological systems. These measurements are even enabling enhanced analyses of complex soil microbial communities, which are the most complex microbial systems known to date. Multi-omic analyses, however, do have sample preparation challenges, since separate extractions are typically needed for each omic study, thereby greatly amplifying the preparation time and amount of sample required. To address this limitation, a 3-in-1 method for the simultaneous extraction of metabolites, proteins, and lipids (MPLEx) from the same soil sample was created by adapting a solvent-based approach. This MPLEx protocol has proven to be both simple and robust for many sample types, even when utilized for limited quantities of complex soil samples. The MPLEx method also greatly enabled the rapid multi-omic measurements needed to gain a better understanding of the members of each microbial community, while evaluating the changes taking place upon biological and environmental perturbations.

A protocol is presented for simultaneously extracting metabolites, proteins, and lipids from a single soil sample, allowing reduced sample preparation times and enabling multi-omic mass spectrometry analyses of samples with limited quantities.

멀티-omic 토양 샘플의 분석을 위한 MPLEx 프로토콜

Mass spectrometry (MS)-based integrated metaproteomic, metabolomic, and lipidomic (multi-omic) studies are transforming our ability to understand and ...

Separation of Aldehydes and Reactive Ketones from Mixtures Using a Bisulfite Extraction Protocol

The purification of organic compounds is an essential component of routine synthetic operations. The ability to remove contaminants into an aqueous layer by generating a charged structure provides an opportunity to use extraction as a simple purification technique. By combining the use of a miscible organic solvent with saturated sodium bisulfite, aldehydes and reactive ketones can be successfully transformed into charged bisulfite adducts that can then be separated from other organic components of a mixture by the introduction of an immiscible organic layer. Here, we describe a simple protocol for the removal of aldehydes, including sterically-hindered neopentyl aldehydes and some ketones, from chemical mixtures. Ketones can be separated if they are sterically unhindered cyclic or methyl ketones. For aliphatic aldehydes and ketones, dimethylformamide is used as the miscible solvent to improve removal rates. The bisulfite addition reaction can be reversed by basification of the aqueous layer, allowing for the re-isolation of the reactive carbonyl component of a mixture.

Here, we present a protocol to remove aldehydes and reactive ketones from mixtures by a liquid-liquid extraction protocol directly with saturated sodium bisulfite in a miscible solvent. This combined protocol is rapid and facile to perform. The aldehyde or ketone can be re-isolated by the basification of the aqueous layer.

알 데히드 류와 Ketones 반응 황산 추출 프로토콜을 사용 하 여 혼합물에서 분리

The purification of organic compounds is an essential component of routine synthetic operations. The ability to remove contaminants into an aqueous layer ...

Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance

Metal-organic frameworks (MOFs) are a class of porous inorganic materials with promising properties in gas storage and separation, catalysis and sensing. However, the main issue limiting their applicability is their poor stability in humid conditions. The common methods to overcome this problem involve the formation of strong metal-linker bonds by using highly charged metals, which is limited to a number of structures, the introduction of alkylic groups to the framework by post-synthetic modification (PSM) or chemical vapour deposition (CVD) to enhance overall hydrophobicity of the framework. These last two usually provoke a drastic reduction of the porosity of the material. These strategies do not permit to exploit the properties of the MOF already available and it is imperative to find new methods to enhance the stability of MOFs in water while keeping their properties intact. Herein, we report a novel method to enhance the water stability of MOF crystals featuring Cu2(O2C)4&#160;paddle-wheel units, such as HKUST (where HKUST stands for Hong Kong University of Science &#38; Technology), with the catechols functionalized with alkyl and fluoro-alkyl chains. By taking advantage of the unsaturated metal sites and the catalytic catecholase-like activity of CuII ions, we are able to create robust hydrophobic coatings through the oxidation and subsequent polymerization of the catechol units on the surface of the crystals under anaerobic and water-free conditions without disrupting the underlying structure of the framework. This approach not only affords the material with improved water stability but also provides control over the function of the protective coating, which enables the development of functional coatings for the adsorption and separations of volatile organic compounds. We are confident that this approach could also be extended to other unstable MOFs featuring open metal sites.

Robust functional catechol coatings were produced in one step by direct reaction of the material known as HKUST with synthetic catechols under anaerobic conditions. The formation of homogeneous coatings surrounding the entire crystal is ascribed to the biomimetic catalytic activity of Cu(II) dimers on the external surface of the crystals.

향상 된 수 분 저항 금속-유기 프레임 워크의 표면 기능화

Metal-organic frameworks (MOFs) are a class of porous inorganic materials with promising properties in gas storage and separation, catalysis and sensing. ...

Automation of a Positron-emission Tomography (PET) Radiotracer Synthesis Protocol for Clinical Production

The development of new positron-emission tomography (PET) tracers is enabling researchers and clinicians to image an increasingly wide array of biological targets and processes. However, the increasing number of different tracers creates challenges for their production at radiopharmacies. While historically it has been practical to dedicate a custom-configured radiosynthesizer and hot cell for the repeated production of each individual tracer, it is becoming necessary to change this workflow. Recent commercial radiosynthesizers based on disposable cassettes/kits for each tracer simplify the production of multiple tracers with one set of equipment by eliminating the need for custom tracer-specific modifications. Furthermore, some of these radiosynthesizers enable the operator to develop and optimize their own synthesis protocols in addition to purchasing commercially-available kits. In this protocol, we describe the general procedure for how the manual synthesis of a new PET tracer can be automated on one of these radiosynthesizers and validated for the production of clinical-grade tracers. As an example, we use the ELIXYS radiosynthesizer, a flexible cassette-based radiochemistry tool that can support both PET tracer development efforts, as well as routine clinical probe manufacturing on the same system, to produce [18F]Clofarabine ([18F]CFA), a PET tracer to measure in vivo deoxycytidine kinase (dCK) enzyme activity. Translating a manual synthesis involves breaking down the synthetic protocol into basic radiochemistry processes that are then translated into intuitive chemistry &#34;unit operations&#34; supported by the synthesizer software. These operations can then rapidly be converted into an automated synthesis program by assembling them using the drag-and-drop interface. After basic testing, the synthesis and purification procedure may require optimization to achieve the desired yield and purity. Once the desired performance is achieved, a validation of the synthesis is carried out to determine its suitability for the production of the radiotracer for clinical use.

Automation of a Positron-emission Tomography PET Radiotracer Synthesis Protocol for Clinical Production

Positron-emission tomography (PET) imaging sites that are involved in multiple early clinical research trials need robust and versatile radiotracer manufacturing capabilities. Using the radiotracer [18F]Clofarabine as an example, we illustrate how to automate the synthesis of a radiotracer using a flexible, cassette-based radiosynthesizer and validate the synthesis for clinical use.

양전자 방출 단층 촬영 (PET) Radiotracer 합성 프로토콜의 임상 생산을 위한 자동화

The development of new positron-emission tomography (PET) tracers is enabling researchers and clinicians to image an increasingly wide array of biological ...