This work was supported by the New Professor Research Foundation Program, funded by Gyeongsang National University (Grant Number 2015-04-020).

공장 페놀 유래 고분자 염료의 1. 준비 <ol><li> 100 mM의 아세트산 나트륨 완충액 (pH 5.0) 및 무수 에탄올 8 ㎖를 32 ㎖의 카테킨 수화물 (0.1 g) - 카테 콜 (0.1 g) 및 (+) 녹인다. </li><li> T. 10 mg을 추가 catechol-과 카테킨 함유 버퍼에 베르의 락카. 격렬하게 혼합 사각형 페트리 접시에 솔루션을 붓는다. 24 시간 동안 진탕 배양기 (25 회전)에 실온에서 접시를 품어. 짙은 검정색 투명의 용액의 색상의 극적인 변화는 락카 유도 커플 링 반응 후 육안으로 관찰 할 수있다. </li><li> 불용성 고분자 입자를 스핀 다운하기 위해 20,000 XG에서 10 분 동안 솔루션을 원심 분리기. 더 탈염에 대한 깊은 블랙 뜨는을 사용합니다. </li><li> 5 kDa의 한외 여과 디스크와 반응 액을 탈염. 한외 여과 내지 20 ㎖의 반응 부피를 농축 한 후, 증류수 300 ㎖에 첨가하여, 반응 완충액을 교환. 마지막으로, 여과하여, 25 ㎖의 상기 용액의 부피를 농축시킨다. </li></ol> 회색 케라틴 헤어 2. 염색 솔루션 <ol><li> 다음 여섯 가지 폴리머 솔루션을 준비 : 고분자 염료, 고분자 염료 / 다음날에 FeSO4, 고분자 염료 / 다음날에 FeSO4의 pH 3 물, 고분자 염료 / 다음날에 FeSO4 pH를 11 물, 고분자 염료 / 병용했을 아세트산 4, 및 고분자 염료 / 병용했을 암모니아 4. <ol><li> 중합체 염료, 탈염 중합체 염료 (1.4) 1 ㎖ 증류수 5 mL를 섞는다. </li><li> 매염제 솔루션의 단계 2.1.1에서 혼합물에 다음날에 FeSO4의 0.33 g을 추가합니다. 격렬하게 소용돌이 완전히 다음날에 FeSO4를 용해한다. </li><li> pH를 3 ~ 11 수용액의 경우, 1 N 염산 또는 1 N의 NaOH를 사용하여 5 ㎖의 증류수의 pH를 조정한다. 그런 다음 탈염 고분자 염료 (1.4) 다음날에 FeSO4의 0.33 g 1 ㎖를 추가합니다. </li><li> 아세트산 산성 또는 암모니아 처리 솔루션의 경우, GL 1.0 ㎖의 혼합acial 아세트산 또는 증류수 5 mL를 암모니아수 용액 1.0. 그런 다음 탈염 고분자 염료 (1.4) 다음날에 FeSO4의 0.33 g 1 ㎖를 추가합니다. </li></ol></li><li> 의 머리를 흡수하기 위해, 또는 다음날에 FeSO4의 0.33 g없는 증류수 6 ml의에 카테킨 수화물 (0.1 g) - 식물 단량체를 들어, 카테 콜 (0.1 g) 및 (+)를 섞는다. </li><li> 즉시 단계 2.1 및 2.2에서 염색 솔루션이 준비 될 때, 완전히 솔루션에서 5 cm 긴 회색 머리카락 다발 (0.2 g)을 흡수. 2.5 시간 동안 진탕 배양기 (160 RPM)에서 32 ° C에서 머리 다발을 품어. </li><li> 그 후, 모발 다발을 꺼내 흐르는 물로 씻어. 습기를 제거하기 위해 전자 헤어 드라이어를 사용합니다. 중합체 염료에 의한 색상의 변화를 육안으로 가시화 될 수있다. <ol><li> 색 파라미터를 얻기 위해 (즉, L *, a * 및는 B *), 제조자의 프로토콜에 따라 종래의 색채를 채용한다. 머리 t을 구겨따라서 이들을 색채의 렌즈로 측정 될 수 있도록 공으로 resses. 색도계 렌즈와 머리의 다른 지역에이 과정을 반복합니다. </li><li> 각 염색 머릿 일곱 번 컬러의 파라미터를 측정한다. 평균 및 매개 변수의 표준 편차를 계산합니다. 식을 사용하여 ΔE를 계산한다 : [(100 - L의 *) 2 + (a *) 2 + (b *) 2] 1/2. </li></ol></li></ol> 3. 색상 내구성 테스트 <ol><li> 40ml의 증류수에 황산 도데 실 나트륨 (SDS) 200 mg을 용해. 실온에서 5 분간 SDS 함유 물에 완전히 염색 된 모발을 담근다. 머리 다발을 꺼내 한 후 세제를 제거하기에 충분한 수돗물로 씻어. 습기를 제거하기 위해 전자 헤어 드라이어를 사용합니다. </li><li> 색 파라미터를 얻기 위해 (즉, L *, a * 및 B는 *)에 따른 manufactur의 종래의 색채를 채용어의 프로토콜입니다. 같은 염색 머리를 한 번 더 단계 3.1에 설명 된 균열을 반복 한 후 다시 매개 변수를 측정합니다. </li><li> 증류수 40 ㎖에 800 mg의 SDS를 녹인다. 단계 3.1에 기재된 바와 같이, 더욱 동일한 염색 된 머리 회 침지 반복한다. 전반적으로, SDS 용액을 4 회 총 염색 각 머리칼을 치료. </li></ol>

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The authors declare that they have no competing financial interests.

흥미롭게도, 우리의 방법은 천연 페놀의 산화제에 의한 중합와 각질 머리를 염색하는 데 걸린 시간을 감소시켰다. 그것은 또한 pH를 변경하고 매염제인가와 중합체 염료의 간단한 조작을 통해 머리에 다양한 색상을 유도. 식물 페놀의 락카 - 촉매 산화와 각질 머리의 현장 배양에 효과적인 염색 (7)를 달성하기 위해 지나치게 긴 배양 시간이 필요합니다. 느린 ?...

Laccases는 페놀과 폴리 페놀 화합물 대한 활성 옥시 다제이다. 그들은 식물, 균류, 곤충, 박테리아 등 다양한 생물에서 발견되었습니다. 그들의 효소 활동은 여러 형태 발생 현상 일에 기여한다. 효소는 또한 작은 유기물을 고체 표면에 결합되는 라디칼의 형성의 결과로, 기판의 단 전자 산화 촉매. 이러한 커플 링 프로세스는 올리고머 및 폴리머의 합성으로 이어질 및 락카 기판은 식물 페놀과 같은 천연 소스에서 경우 3., 효소 반응이 녹색 화학에 대해 큰 관심의 관능 2, 표면. 여기, 두 반응물과 촉매는 천연 자원으로부터 있습니다. 또한, 얻어진 제품은 전체 반응은 천연 페놀의 생체 내 합성 모방 때문에 식물 리그닌, 폴리 (flavono 중합체를 포함한 상기 천연물 유사한ID)와 상기 부식 - 작은 식물 페놀 화합물 고도로 가교 다제 - 유도 라디칼 커플 4이다. 식물 유래의 페놀 락카 - 촉매 커플 링 반응에서 파생 된 제품은 현장에서 배양 백발을 통해 염색하는데 사용될 수 있고 대안으로 시판 한 염료로 개발 될 수있다. 상업적 헤어 염색 에이전트 피의 -phenylenediamine (PPD)에 기초하기 때문에 이러한 대안은 중요 PPD 관련 디아민 화합물, 수소, 유독성 발암 것으로 나타났다 옥사이드, 인간 5, 6 알러지.에서 락카 - 촉매 커플 링 반응은 laccases 식물 페놀 기능적 각각 과산화수소 및 P의 -phenylenediamine 7 대체. 그러나, 락카 기반 시스템의 염색 속도가 상업용 하나보다 훨씬 느리다. 일반적으로, PPD 계 염색 제제는 달성 한 시간 미만을 필요각질 머리에 효과적인 색상 변경은 락카 기반 반응이 하룻밤 배양 (7)를 필요로한다. 느린 동역학 염색은 두 가지 현상을 설명 할 수있다. 첫째, 낮은 pH 완충의 사용 (예를 들어, pH가 5) 락카 제 활성을 최대화하기 위해, 따라서 매트릭스에 염료의 깊은 침투를 억제 케라틴 매트릭스 부종의 정도를 감소하는 것으로 관찰되었다. 실제로, pH가 높은 상태에서 진행 염색 반응을 허용 화제는 상업적 모발 염색 제품 (8)에 통합 될 것으로 나타났다. 둘째, 중합 반응 동안 케라틴 표면에 강한 흡수를 나타내는 발색단 가능한 분자의 개수는 배양 시간 (중합 예 정도)에 비례하는 것으로 밝혀졌다. 예를 들어, 도파민 polydopamine로의 변환은 흑색 (9)의 형성에 수반되었다 많은 표면에 강한 접착을 유도하는 것으로 나타났다. &lt;/ P&gt; 현재의 연구에서, T.에서 얻은 고분자 제품을 미리은 합성 카테킨과 카테 콜 락카 - 촉매 산화 베르 염색 각질 머리를 치료하는 데 사용되었다. 우리는 중합체의 흡착 능력은 모노머 식물 페놀보다 훨씬 더 강할 것이라는 그들은 초기에 저 분자량 올리고머를 형성하는 것으로 가정 하였다. 결과는 프리 - 합성 폴리머를 사용하는 경우, 효소 산화력이 더 이상 필요했던 것을 입증 없다. 이것은 pH가 조절 될 수 있고 그 금속 이온은 효소 활성에 관계없이, 헤어 염색 치료에 사용될 수 있음을 나타낸다. 이 프로토콜은 친환경 및 신 재생 식물 유래 페놀 (그림 1)을 사용하는 동안 색상의 다양 한 음영에서 각질 머리를 염색하는 간단하고 빠른 방법을 제공한다.

<table border="0" cellpadding="0" cellspacing="0" width="802">
	<tbody>
		<tr height="32">
			<td height="32" style="height:32px;width:208px;">Sodium dodecyl Sulfate</td>
			<td style="width:205px;">Promega</td>
			<td style="width:208px;">H5114</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">Laccase from Trametes versicolor</td>
			<td style="width:205px;">Sigma</td>
			<td style="width:208px;">38429-1G</td>
			<td style="width:181px;">Enzyme activity is denoted as 0.53 U/mg</td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">(+)-catechin hydrate</td>
			<td style="width:205px;">Sigma</td>
			<td style="width:208px;">C1251-5G</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">1,2-dihydroxybenzene (catechol)</td>
			<td style="width:205px;">Sigma</td>
			<td style="width:208px;">135011-5G</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">Ammonia water&#160;</td>
			<td style="width:205px;">Duksan</td>
			<td style="width:208px;">701</td>
			<td style="width:181px;">Ammonia contents is denoted as 25 ~ 30%</td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">Acetic acid, glacial</td>
			<td style="width:205px;">Duksan</td>
			<td style="width:208px;">448</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">Iron (II) sulfate heptahydrate</td>
			<td style="width:205px;">JUNSEI</td>
			<td style="width:208px;">83380-1250</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Ultracell 5kDa</td>
			<td style="width:205px;">Amicon</td>
			<td style="width:208px;">PLCC06210</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Stirred ultrafiltration cells</td>
			<td style="width:205px;">Millipore</td>
			<td style="width:208px;">Model 8200</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Human gray hair</td>
			<td style="width:205px;">PheonixKorea</td>
			<td style="width:208px;">Not available</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Colorimeter</td>
			<td style="width:205px;">SPEC</td>
			<td style="width:208px;">JCS-10</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Square dish</td>
			<td style="width:205px;">SPL</td>
			<td style="width:208px;">10125</td>
			<td style="width:181px;">125 * 125 * 20 (mm)</td>
		</tr>
	</tbody>
</table>

synthesis of plant phenol-derived polymeric dyes for direct or mordant-based hair dyeing

식물 페놀의 곰팡이 락카 - 촉매 중합의 제품과 각질 머리의 현장 배양에 통해 효과적인 머리 염색은 이전에 증명되었다. 그러나, 염색 처리는 모발 염색 상용 제품에 비해 완료하는 데 오랜 시간이 걸린다. 이러한 병목 현상을 극복하기 위해, 또는 매염제 제제 (예를 들면, 다음날에 FeSO4), 여기에서 다양한 색상 및 색조 영구 케라틴 모발 염색을 달성하기 위해 사용 하였다없이 어느 카테킨 및 카테 콜의 락카 베르 Trametes의 산화 반응의 중합체 제품, 중고 합성 . 산성 아세트산 나트륨 완충액에서 락카 동작 식물 페놀과 반응 후 결합 깊은 흑색 착색되었다. 착색 염료 제품은 탈염 및 한외 여과로 농축시켰다. 또는 매염제 에이전트없이 염료, 회색 머리카락 위스콘신 ΔE 값 (즉, 색차 값)의 상당한 증가를 야기얇은 2.5 시간. 또한, 다른 케라틴 색상 및 색조가 매염하여 pH 변화에 따라 유도 하였다. 염색 머리는 또한 우리의 방법은 영원한 머리 염색을 야기 할 수 있음을 나타냅니다, 세제 처리에 강한 저항성을 나타냈다. 전반적으로, 우리의 작업은 상업 독성 디아민 계 염료에 대한 대안으로 환경 친화적 인 헤어 염색 방법을 개발에 새로운 통찰력을 제공하고있다 .

우선, 중합체 염료의 염색 능력은 식물 유래의 단량체 (예, 카테킨, 및 카테 콜)의 것과 비교 하였다. 모발의 타고난 그레이 색 (데이터 미도시) 식물 단량체 매우 안정적으로 유지하면서 고분자 염료 회색 모발 케라틴 (도 2a 및도 3)의 색상에 큰 변화를 야기. 고분자 제품의 염색 능력에 에이전트를 매염의 효과는 다음 평가 하였...

Watch this Scientific Journal Video about Synthesis of Plant Phenol-derived Polymeric Dyes for Direct or Mordant-based Hair Dyeing at JoVE.com

Synthesis of Plant Phenol-derived Polymeric Dyes for Direct or Mordant-based Hair Dyeing

Here, we present a protocol to use pre-synthesized polymeric products derived from fungal laccase-catalyzed polymerization of plant phenols, either with or without mordant agents (e.g., FeSO4), to induce detergent-resistant keratin hair dyeing within 2.5 hours.

직접 또는 모던 기반 머리 염색에 대한 공장 페놀 유래 고분자 염료의 합성

Effective hair dyeing through in situ incubation of keratin hair with the products of fungal laccase-catalyzed polymerization of plant phenols has been ...

synthesis-plant-phenol-derived-polymeric-dyes-for-direct-or-mordant

Research

JoVE Journal

Chemistry

9.2K 조회수.  Gyeongsang National University. Here, we present a protocol to use pre-synthesized polymeric products derived from fungal laccase-catalyzed polymerization of plant phenols, either with or without mordant agents (e.g., FeSO4), to induce detergent-resistant keratin hair dyeing within 2.5 hours.

비디오: Synthesis of Plant Phenol-derived Polymeric Dyes for Direct or Mordant-based Hair Dyeing

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes

Functionalized naphthalenes have applications in a variety of research fields ranging from the synthesis of natural or biologically active molecules to the preparation of new organic dyes. Although numerous strategies have been reported to access naphthalene scaffolds, many procedures still present limitations in terms of incorporating functionality, which in turn narrows the range of available substrates. The development of versatile methods for direct access to substituted naphthalenes is therefore highly desirable.
The Diels-Alder (DA) cycloaddition reaction is a powerful and attractive method for the formation of saturated and unsaturated ring systems from readily available starting materials. A new microwave-assisted intramolecular dehydrogenative DA reaction of styrenyl derivatives described herein generates a variety of functionalized cyclopenta[b]naphthalenes that could not be prepared using existing synthetic methods. When compared to conventional heating, microwave irradiation accelerates reaction rates, enhances yields, and limits the formation of undesired byproducts.
The utility of this protocol is further demonstrated by the conversion of a DA cycloadduct into a novel solvatochromic fluorescent dye via a Buchwald-Hartwig palladium-catalyzed cross-coupling reaction. Fluorescence spectroscopy, as an informative and sensitive analytical technique, plays a key role in research fields including environmental science, medicine, pharmacology, and cellular biology. Access to a variety of new organic fluorophores provided by the microwave-assisted dehydrogenative DA reaction allows for further advancement in these fields.

Microwave-assisted intramolecular dehydrogenative Diels-Alder (DA) reactions provide concise access to functionalized cyclopenta[b]naphthalene building blocks. The utility of this methodology is demonstrated by one-step conversion of the dehydrogenative DA cycloadducts into novel solvatochromic fluorescent dyes via Buchwald-Hartwig palladium-catalyzed cross-coupling reactions.

작용 Naphthalenes / Solvatochromic의 염료의 합성을위한 전자 레인지를 이용한 분자 Dehydrogenative Diels-앨더 반응

Functionalized naphthalenes have applications in a variety of research fields ranging from the synthesis of natural or biologically active molecules to ...

연구

화학

Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities

Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are rapidly oxidized, for example by atmospheric oxygen, to indigo type dyes. This reaction enables fast and easy screening in vivo without isolation or purification of enzymes, as well as rapid tests on agar plates or in solution (e.g., blue-white screening, micro-wells) and is used in biochemistry, histochemistry, bacteriology and molecular biology. Unfortunately the synthesis of such substrates proved to be difficult, due to various side reactions and the low reactivity of the indoxyl hydroxyl function. Especially for glucose type structures low yields were observed. Our novel approach employs indoxylic acid ester as key intermediates. Indoxylic acid esters with varied substitution patterns were prepared on scalable pathways. Phase transfer glycosylations with those acceptors and peracetylated glycosyl halides can be performed under common conditions in high yields. Ester cleavage and subsequent mild silver mediated glycosylation yields the peracetylated indoxyl glycosides in high yields. Finally deprotection is performed according to Zempl&#233;n.

Indoxyl glycosides are well-established and widely used tools for enzyme screening and enzyme activity monitoring. Especially for glucose type structures previous syntheses proved to be challenging and low yielding. Our novel approach employs indoxylic acid esters as precious intermediates to yield a considerable number of indoxyl glycosides in good yields.

Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are ...

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products

The guanidine functional group, displayed most prominently in the amino acid arginine, one of the fundamental building blocks of life, is an important structural element found in many complex natural products and pharmaceuticals. Owing to the continual discovery of new guanidine-containing natural products and designed small molecules, rapid and efficient guanidinylation methods are of keen interest to synthetic and medicinal organic chemists. Because the nucleophilicity and basicity of guanidines can affect subsequent chemical transformations, traditional, indirect guanidinylation is typically pursued. Indirect methods commonly employ multiple protection steps involving a latent amine precursor, such as an azide, phthalimide, or carbamate. By circumventing these circuitous methods and employing a direct guanidinylation reaction early in the synthetic sequence, it was possible to forge the linear terminal guanidine containing backbone of clavatadine A to realize a short and streamlined synthesis of this potent factor XIa inhibitor. In practice, guanidine hydrochloride is elaborated with a carefully constructed protecting array that is optimized to survive the synthetic steps to come. In the preparation of clavatadine A, direct guanidinylation of a commercially available diamine eliminated two unnecessary steps from its synthesis. Coupled with the wide variety of known guanidine protecting groups, direct guanidinylation evinces a succinct and efficient practicality inherent to methods that find a home in a synthetic chemist&#39;s toolbox.

Here, we present a protocol for direct, early stage guanidinylation that enables rapid total synthesis of aminoguanidine-containing small organic molecules. An advanced synthetic intermediate used in the synthesis of a blood coagulation factor XIa inhibitor was prepared using this protocol.

복잡한 아미노 구아니딘 함유 천연 제품의 합성에 대한 직접, 초기 단계 Guanidinylation 프로토콜

The guanidine functional group, displayed most prominently in the amino acid arginine, one of the fundamental building blocks of life, is an important ...

Hydroquinone Based Synthesis of Gold Nanorods

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the synthetic methods for the preparation of gold nanorods are still not fully optimized. In this paper we describe a new, highly efficient, two-step protocol based on the use of hydroquinone as a mild reducing agent. Our approach allows the preparation of nanorods with a good control of size and aspect ratio (AR) simply by varying the amount of hexadecyl trimethylammonium bromide (CTAB) and silver ions (Ag+) present in the "growth solution". By using this method, it is possible to markedly reduce the amount of CTAB, an expensive and cytotoxic reagent, necessary to obtain the elongated shape. Gold nanorods with an aspect ratio of about 3 can be obtained in the presence of just 50 mM of CTAB (versus 100 mM used in the standard protocol based on the use of ascorbic acid), while shorter gold nanorods are obtained using a concentration as low as 10 mM.

This paper describes a protocol for the synthesis of gold nanorods, based on the use of hydroquinone as reducing agent, plus the different mechanisms for controlling their size and aspect ratio.

금 나노 막대의 하이드로 퀴논 기반 합성

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the ...

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single molecule level. An electrostatic self-assembly and covalent fixation (ESA-CF) process is used for the synthesis of the cyclic poly(tetrahydrofuran) (poly(THF)). The diffusive motion of individual cyclic polymer chains in a melt state is visualized using single molecule fluorescence imaging by incorporating a fluorophore unit in the cyclic chains. The diffusive motion of the chains is quantitatively characterized by means of a combination of mean-squared displacement (MSD) analysis and a cumulative distribution function (CDF) analysis. The cyclic polymer exhibits multiple-mode diffusion which is distinct from its linear counterpart. The results demonstrate that the diffusional heterogeneity of polymers that is often hidden behind ensemble averaging can be revealed by the efficient synthesis of the cyclic polymers using the ESA-CF process and the quantitative analysis of the diffusive motion at the single molecule level using the MSD and CDF analyses.

A protocol for the synthesis and characterization of diffusive motion of cyclic polymers at the single molecule level is presented.

단일 분자 수준에서 순환 고분자의 합성 및 용융 상태에서 그들의 확산 운동의 특성

We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single ...

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of Chalcogenidoplumbates(II or IV)

The phases of &#34;PbCh2&#34; (Ch = Se, Te) are obtained from solid-state syntheses (i.e., by the fusion of the elements under inert conditions in silica glass ampules). Reduction of such phases by elemental alkaline metals in amines affords crystalline chalcogenidoplumbate(II) salts comprised of [PbTe3]2- or [Pb2Ch3]2- anions, depending upon which sequestering agent for the cations is present: crown ethers, like 18-crown-6, or cryptands, like [2.2.2]crypt. Reactions of solutions of such anions with transition-metal compounds yield (poly-)chalcogenide anions or transition-metal chalcogenide clusters, including one with a &#181;-PbSe ligand (i.e., the heaviest-known CO homolog).
In contrast, the solid-state synthesis of a phase of the nominal composition &#34;K2PbSe2&#34; by successive reactions of the elements and by the subsequent solvothermal treatment in amines yields the first non-oxide/halide inorganic lead(IV) compound: a salt of the ortho-selenidoplumbate(IV) anion [PbSe4]4-. This was unexpected due to the redox potentials of Pb(IV) and Se(-II). Such methods can further be applied to other elemental combinations, leading to the formation of solutions with binary [HgTe2]2- or [BiSe3]3- anions, or to large-scale syntheses of K2Hg2Se3 or K3BiSe3 via the solid-state route.
All compounds are characterized by single-crystal X-ray diffraction and elemental analysis; solutions of plumbate salts can be investigated by 205Pb and 77Se or 127Te NMR techniques. Quantum chemical calculations using density functional theory methods enable energy comparisons. They further allow for insights into the electronic configuration and thus, the bonding situation. Molecular Rh-containing Chevrel-type compounds were found to exhibit delocalized mixed valence, whereas similar telluridopalladate anions are electron-precise; the cluster with the &#181;-PbSe ligand is energetically favored over a hypothetical CO analog, in line with the unsuccessful attempt at its synthesis. The stability of formal Pb(IV) within the [PbSe4]4- anion is mainly due to a suitable stabilization within the crystal lattice.

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV

The synthesis of chalcogenidoplumbates(II,IV) via the in situ reduction of nominal "PbCh2" (Ch = Chalcogen) and via a solid-state reaction and subsequent solvothermal reactions is presented. Additionally, reactivities of plumbate(II) solutions are portrayed, which yield the heaviest-known CO homolog known to date: the &#181;-PbSe ligand.

고체 및 솔루션 기반의 기술 결합 : 합성 및 Chalcogenidoplumbates의 반응성 (II 또는 IV)

The phases of &#34;PbCh2&#34; (Ch = Se, Te) are obtained from solid-state syntheses (i.e., by the fusion of the elements under inert conditions in silica ...

Direct Imaging of Laser-driven Ultrafast Molecular Rotation

We present a method for visualizing laser-induced, ultrafast molecular rotational wave packet dynamics. We have developed a new 2-dimensional Coulomb explosion imaging setup in which a hitherto-impractical camera angle is realized. In our imaging technique, diatomic molecules are irradiated with a circularly polarized strong laser pulse. The ejected atomic ions are accelerated perpendicularly to the laser propagation. The ions lying in the laser polarization plane are selected through the use of a mechanical slit and imaged with a high-throughput, 2-dimensional detector installed parallel to the polarization plane. Because a circularly polarized (isotropic) Coulomb exploding pulse is used, the observed angular distribution of the ejected ions directly corresponds to the squared rotational wave function at the time of the pulse irradiation. To create a real-time movie of molecular rotation, the present imaging technique is combined with a femtosecond pump-probe optical setup in which the pump pulses create unidirectionally rotating molecular ensembles. Due to the high image throughput of our detection system, the pump-probe experimental condition can be easily optimized by monitoring a real-time snapshot. As a result, the quality of the observed movie is sufficiently high for visualizing the detailed wave nature of motion. We also note that the present technique can be implemented in existing standard ion imaging setups, offering a new camera angle or viewpoint for the molecular systems without the need for extensive modification.

We present a protocol for creating a real-time movie of a molecular rotational wave packet using a high-resolution Coulomb explosion imaging setup.

레이저 기반 초고속 분자 회전의 직접 이미징

We present a method for visualizing laser-induced, ultrafast molecular rotational wave packet dynamics. We have developed a new 2-dimensional Coulomb ...

Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Covalent Organic Frameworks (COFs) are a class of porous covalent materials which are frequently synthesized as unprocessable crystalline powders. The first COF was reported in 2005 with much effort centered on the establishment of new synthetic routes for its preparation. To date, most available synthetic methods for COF synthesis are based on bulk mixing under solvothermal conditions. Therefore, there is increasing interest in developing systematic protocols for COF synthesis that provide for fine control over reaction conditions and improve COF processability on surfaces, which is essential for their use in practical applications. Herein, we present a novel microfluidic-based method for COF synthesis where the reaction between two constituent building blocks, 1,3,5-benzenetricarbaldehyde (BTCA) and 1,3,5-tris(4-aminophenyl)benzene (TAPB), takes place under controlled diffusion conditions and at room temperature. Using such an approach yields sponge-like, crystalline fibers of a COF material, hereafter called MF-COF. The mechanical properties of MF-COF and the dynamic nature of the approach allow the continuous production of MF-COF fibers and their direct printing onto surfaces. The general method opens new potential applications requiring advanced printing of 2D or 3D COF structures on flexible or rigid surfaces.

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

We present a novel microfluidic-based method for synthesis of covalent organic frameworks (COFs). We demonstrate how this approach can be used to produce continuous COF fibers, and also 2D or 3D COF structures on surfaces.

Microfluidic 기반 CODMs의 합성 : COF 섬유의 지속적인 생산과 표면의 직접 인쇄를위한 도구

Covalent Organic Frameworks (COFs) are a class of porous covalent materials which are frequently synthesized as unprocessable crystalline powders. The ...

Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain

Barium titanate (BaTiO3, hereafter BT) is an established ferroelectric material first discovered in the 1940s and still widely used because of its well-balanced ferroelectricity, piezoelectricity, and dielectric constant. In addition, BT does not contain any toxic elements. Therefore, it is considered to be an eco-friendly material, which has attracted considerable interest as a replacement for lead zirconate titanate (PZT). However, bulk BT loses its ferroelectricity at approximately 130 &#176;C, thus, it cannot be used at high temperatures. Because of the growing demand for high-temperature ferroelectric materials, it is important to enhance the thermal stability of ferroelectricity in BT. In previous studies, strain originating from the lattice mismatch at hetero-interfaces has been used. However, the sample preparation in this approach requires complicated and expensive physical processes, which are undesirable for practical applications.
In this study, we propose a chemical synthesis of a porous material as an alternative means of introducing strain. We synthesized a porous BT thin film using a surfactant-assisted sol-gel method, in which self-assembled amphipathic surfactant micelles were used as an organic template. Through a series of studies, we clarified that the introduction of pores had a similar effect on distorting the BT crystal lattice, to that of a hetero-interface, leading to the enhancement and stabilization of ferroelectricity. Owing to its simplicity and cost effectiveness, this fabrication process has considerable advantages over conventional methods.

Here, we present a protocol for the synthesis of porous barium titanate (BaTiO3) thin film by a surfactant-assisted sol-gel method, in which self-assembled amphipathic surfactant micelles are used as an organic template.

바 륨 다공성 타이타늄 박막 및 다공성 유도 된 긴장에 의해 Ferroelectric 단계의 열 안정화의 화학 합성

Barium titanate (BaTiO3, hereafter BT) is an established ferroelectric material first discovered in the 1940s and still widely used because of its ...

Synthesis of Substrate-Bound Au Nanowires Via an Active Surface Growth Mechanism

Advancing synthetic capabilities is important for the development of nanoscience and nanotechnology. The synthesis of nanowires has always been a challenge, as it requires asymmetric growth of symmetric crystals. Here, we report a distinctive synthesis of substrate-bound Au nanowires. This template-free synthesis employs thiolated ligands and substrate adsorption to achieve the continuous asymmetric deposition of Au in solution at ambient conditions. The thiolated ligand prevented the Au deposition on the exposed surface of the seeds, so the Au deposition only occurs at the interface between the Au seeds and the substrate. The side of the newly deposited Au nanowires is immediately covered with the thiolated ligand, while the bottom facing the substrate remains ligand-free and active for the next round of Au deposition. We further demonstrate that this Au nanowire growth can be induced on various substrates, and different thiolated ligands can be used to regulate the surface chemistry of the nanowires. The diameter of the nanowires can also be controlled with mixed ligands, in which another &#34;bad&#34; ligand could turn on the lateral growth. With the understanding of the mechanism, Au nanowire-based nanostructures can be designed and synthesized.

We report a solution-based method to synthesize substrate-bound Au nanowires. By tuning the molecular ligands used during the synthesis, the Au nanowires can be grown from various substrates with different surface properties. Au nanowire-based nanostructures can also be synthesized by adjusting the reaction parameters.