Mali anıyoruz destek ANR (ANR-15-CE29-0020-01, ACTIV-CF-LAN), CNRS, ICMR, Université de Reims Champagne Ardenne, ENSCM ve ICGM. Carine Machado ve Anthony Robert EI-MS ve NMR analizi ile yardım için teşekkür.

1. hazırlık malzeme torpidoda dışında başlayan
<ol><li>Gerekli donanımları hazırlamak: fırın kurutulmuş Schlenk tüp manyetik heyecan bar, vakum/inert gaz borusu (argon veya azot) ve manyetik karıştırıcı ile.</li>
	<li>Trifluoromethylated benzofulvene edebiyat13göre hazırlayın.</li>
	<li>Trifluoromethylated benzofulvene (177 mg, 0.65 mmol) tartmak ve manyetik heyecan bar ile donatılmış fırın kurutulmuş Schlenk tüp içine ekleyin.</li>
	<li>Schlenk tüp PTFE liner ile plastik vida kapaklı kapatın ve vakum hattýna baðlayýn.</li>
	<li>Karıştırarak başlatmak ve kuru benzofulvene 10 dk için vakum uygulanır. Sonra vakum argon/azot ile serbest bırakmak ve tekrar vakum uygulayabilirsiniz. Bu işlem 3 kez tekrarlayın. Son olarak, Schlenk tüp argon/azot ile doldurun ve sıkıca kapatın.</li>
	<li>Schlenk tüp argon/azot altında torpido için al.</li>
</ol>2. taze Filed disprosiyum Metal torpidoda içinde hazırlanması
<ol><li>Gerekli donanımları hazırlamak: torpido argon/Azot dengesi, metal dosya, pense, alüminyum folyo, forseps, spatula, tüp bebek ve 2 lastik septa Tartı ile altında.</li>
	<li>Kimyasallar hazırlamak: disprosiyum metal ve susuz AlCl3
</li>
	<li>Benzofulvene ile INSERT Schlenk Tüp, tüp bebek ve 2 lastik septa grubunuzun genel uygulama torpidoda işleme göre torpido içine, Örneğin, küçük bir oda için üç kez 1 dk sonra argon/azot ile serbest bırakmak için vakum uygulanır.</li>
	<li>Doldurmak için torpidoyu katta tartı denge ve bir tabak üzerine üzerine alüminyum folyo bir parça koy.</li>
	<li>Sıkıca disprosiyum metal pense yardımıyla tutun ve onun üst etkin olmayan katman dosyalama tarafından parlak metal yüzey elde etmek için metal bir dosyası ile kaldırın. Bu dosyalanmış metal atmak. Not: kullanın (1) büyük metal parçalar için dosyalama ve pense ve disprosiyum metal diğer metaller ile kontamine değil sırayla Dosya arasında temas kaçının. (2) çapraz bulaşma önlemek için her lanthanide metal için farklı bir metal dosya kullanın. (3) atılan metal tozu ayrı ayrı torpido dışında d. aq HCl çözüm kullanarak su. Dikkat: Disprosiyum aq HCl ile reaksiyon ekzotermik ve hidrojen gazı üretir, bu nedenle açık bir şişe buz banyosu tarafından çevrili disprosiyum gidermek.</li>
	<li>Taze filed disprosiyum metal (82 mg, 0.50 mmol) hazırlamak, Schlenk tüp ekleyin ve bir lastik septum ile tüp kapatın.</li>
	<li>Bir test tüpüne susuz AlCl3 (200 mg, 1,5 mmol) tartmak ve kauçuk septum ile tüp kapatın.</li>
	<li>Schlenk tüp ve test tüpü eldiven kutusundan kaldırın.</li>
</ol>3. başlangıç C-F harekete geçirmek tepki torpidoda dışında
<ol><li>Gerekli donanımları hazırlamak: Vakum/inert gaz hattı (argon veya azot), manyetik karıştırıcı ve kuru 2 mL şırınga iğne ile.</li>
	<li>Kimyasallar hazırlamak: taze kuru THF ve iyot distile.</li>
	<li>Bir duman başlıklı bir manyetik karıştırıcı yukarıda Schlenk tüp klamp ve vakum hattýna baðlayýn. Üç devir vakum/inert gaz argon/azot olumlu bir akış altında Schlenk tüp açmadan önce gerçekleştirin. Manyetik karıştırıcı başlatın.</li>
	<li>Bir duman mahallede AlCl3 test tüpü kelepçe ve inert gaz hattı argon/azot olumlu bir akış altında bir iğne ile bağlanın.</li>
	<li>İyot (10-12 mg) katalitik bir miktar pozitif argon/azot akış altında Schlenk tüp ekleyin.</li>
	<li>Argon/azot altında iğne ile Kuru 2 mL şırınga temizle</li>
	<li>1.5 mL taze distile kuru THF tasfiye Ģırınga kullanarak tutup derin kahverengi çözüm (THF iyot rengini) elde etmek için Schlenk tüp 0.5 mL ekleyin.</li>
	<li>THF kalan 1.0 mL tüp AlCl3biraz sarı bir çözüm için yol açacaktır, dropwise ekleyin. Not: AlCl3kalitesine bağlı olarak THF ek daha fazla veya daha az ekzotermik olabilir.</li>
	<li>Hala sıcak iken, bu AlCl3 çözüm şırınga kullanarak Schlenk tüp test tüpünden aktarın.</li>
	<li>Benzofulvene tam tüketimi kadar karıştırmaya tepki sağlar. Başlangıçta, derin kahverengi renk zamanla koyu yeşil bulanık çözüm dönecek sarı bir çözüm vermek için kaybolur.</li>
	<li>Reaksiyon 1s sonra argon/azot olumlu bir akış altında bir kılcal reaksiyon karışımla örneği alarak ince katmanlı Kromatografi (TLC) tarafından kontrol edin. Petrol eter eluent kullanın. Not: Başlangıç benzofulvene TLC plaka üzerinde parlak sarı ve onun ortadan kalkması kolayca görülebilir.</li>
</ol>4. Nitroalkene ilavesi
<ol><li>4-methoxyphenylnitroalkene edebiyat16göre hazırlayın.</li>
	<li>Bir test tüpünde 4-methoxyphenylnitroalkene (90 mg, 0.50 mmol) tartmak, kauçuk tıpa ile tüp kapatın ve iğne bağlantısı üzerinden vakum satırındaki kuru.</li>
	<li>Benzofulvene (TLC analiz tarafından teyit) tepki karışımı kayboluşundansonra Schlenk tüp argon/azot olumlu bir akış altında Kuru nitroalkene ekleyin. Reaksiyon karışım rengi sarı-yeşil için değiştirilir.</li>
	<li>Reaksiyon TLC analiz, nitroalkene (genellikle 1 saat) tam tüketimi kadar izlemek. Petrol eter/etil asetat 95/5 eluent kullanın.</li>
</ol>5. iş ve arıtma
<ol><li>20 mL dietil eter ile reaksiyon karışımı sulandırmak ve 5 mL 1 molar sulu çözüm açık bir Schlenk tüp hidroklorik asit ile gidermek. Dikkat: Aq HCl ile kalan disprosiyum reaksiyon ekzotermik ve basınç inşa içinde Schlenk neden olabilir hidrojen gazı üretir. Bu nedenle, iyi duman başlık altında açık Schlenk tepki gidermek.</li>
	<li>Reaksiyon Şoklama sonra HCI'yi bir huni aktarın.</li>
	<li>Organik faz konik bir şişeye toplamak. Sulu faz 2 kez 10 mL dietil eter ile yıkama ve Organik faz konik şişeye toplamak.</li>
	<li>MgSO4, filtre içine önceden asılı bir şişesi üzerinde Organik faz kuru ve ham ürün bir turuncu-kahverengi yağ olarak almak için bir rotary Evaporatör üzerinde düşük basınç altında konsantre.</li>
	<li>Silika jel sütun Kromatografi eluent-polar olmayan hidrolize ürün kaldırmak için petrol eter ile başlayan tarafından ham ürün arındırmak. Polarizasyonu en fazla artan 10/1 petrol eter/etil asetat yeni nitro içeren difluoroalkenes verir. Not: sütun Kromatografi uzun bir sütunda ve polarite ve yavaş yavaş artan tarafından gerçekleştirilirken, çözümleme amacıyla diastereoisomers ayırmak zor.</li>
</ol>

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Yazarlar ifşa gerek yok.

Bu iletişim kuralı büyük ölçüde reaktif hava ve nem duyarlı lanthanide metaller ile çalışma gerektirir. Bu nedenle, tüm reaksiyon yordamı kuru inert gaz altında yapılacak ve solventler, dahil olmak üzere tüm başlangıç malzemeler çok temiz ve kuru kullanmadan önce olması gerekir.
Zaten dosyalanmış metaller alımı üzerinde taze dosyalanmış metaller hazırlanması için iki avantajı vardır: (i) adet veya külçe alımı önemli ölçüde daha ekonomik ve (ii) taze d...

Lanthanide metaller düzensiz organik sentezinde geç 1970'lerde1beri kullanılmaktadır. Başlangıçta, bu güçlü azalan bakiyeli ajanlarla, bir redoks potansiyeli Ln3 +olması, yaklaşık-2.3 V, esas olarak huş türü indirimleri aromatik bileşikler ve pinacol reaksiyonlar kaplin istihdam edildi. Bir Artırılmış kullanılabilirlik ve saflık üzerinde 1980'lerden itibaren lanthanide metallerin yanı sıra geliştirme metodolojileri ve hava ve nem duyarlı bileşikleri işlemek için ekipman lanthanide metallerin yeni uygulamalara yol açtı. Doğrudan doğruya--dan Sm metal ve diiodoethane veya iyot yaygın olarak kullanılan SMI2 hazırlanması lanthanide Kimya2' deki bir adımdı. Son yıllarda yeni reaktivite desenleri lanthanide metallerin tarif var, örneğin, karbonil ile allylic halojenürlerden Barbier tipi reaksiyon diaryl Ketonlar4 ya da asil içeren indirgeyici kaplin reaksiyonlar3, bileşikler klorür5, seçici cyclopropanation reaksiyonlar6ve lanthanide metaller grubu 4 metallocenes7,8ile kombinasyonu. Bu çalışmalar lanthanide metaller gelecek vaat eden bir işlevsel grubuna tolerans göstermek ve onların reaktivite reaksiyon koşullarında organik dönüşümleri ince ayar yapmak için uygun reaktifler geliştirmelerde lanthanide Serisi boyunca değişebilir gösterdi.
Organolanthanide kompleksleri ve inorganik lanthanide tuzları ile aromatik ve alifatik karbon-Flor bağları 40 yıl9,10,11C-F harekete geçirmek reaksiyonlarda okudu. 2014 yılında12C-F harekete geçirmek istimal elemental iterbiyum metal ilk raporda ortaya çıktı. Yb regioselective reaksiyon ile p- tetrafluorobenzene ve YbF2göze pentafluorobenzene gösterdi. Daha yakın zamanlarda, çeşitli lanthanide metaller trifluoromethylated benzofulvenes huzurunda ε, seçmeli olarak geniş bir yelpazede aldehitler için yeni tepki ε-difluoropentadienylmetal kompleksler elde etmek için alüminyum klorür ile tepki verebilir göstermiştir difluoroalkenes (Şekil 1)13. Disprosiyum metal kombinasyonu ortaya çıktı ve alüminyum klorür en yüksek verimleri ve en iyi selectivities verdi. Biz burada bir uzantısı electrophiles14, nitroalkenes kullanarak bu eserin regioselectively difluoroalkenes15yeni bir sınıf için önde gelen mevcut.

<table><tbody><tr><td>Dysprosium ingot</td><td>Strem</td><td>93-6637</td><td>Store under nitrogen/argon</td></tr><tr><td>Anhydrous aluminum chloride</td><td>Alfa Aesar</td><td>88488</td><td>Store under nitrogen/argon</td></tr><tr><td>Iodine 99.5% for analysis</td><td>Across Organics</td><td>212491000</td><td></td></tr><tr><td>THF GPR Rectapur</td><td>VWR Chemicals</td><td>28552.324</td><td>Dried and distilled over Na/benzophenone before use</td></tr><tr><td>Glovebox</td><td>MBraun</td><td></td><td>Under nitrogen atmosphere</td></tr></tbody></table>

application of elemental lanthanides in the selective c-f activation of trifluoromethylated benzofulvenes providing access to various difluoroalkenes

Bir karbon-Flor bond polyfluorinated aromatik molekül veya trifluoromethyl içeren yüzeylerde seçici aktivasyonu benzersiz flor içeren moleküller diğer tarafından elde etmek zordur erişme imkanı sunuyor Sentetik yollar. Onlar güçlü Ln-F bağlar biçimi olarak C-F harekete geçirmek için çeşitli Metaller arasında lantanit (Ln) iyi adaylar bulunmaktadır. Lanthanide metaller Mg2 +/Mg redoks çift değerine benzer bir redoks potansiyeli Ln3 +olması, yaklaşık-2.3 V, güçlü azalan bakiyeli ajanlarla vardır. Ayrıca, gelecek vaat eden bir işlevsel grubuna tolerans lanthanide metaller görüntülemek ve onların reaktivite reaksiyon koşullarında organik ve organometalik dönüşümleri ince ayar yapmak için uygun reaktifler geliştirmelerde lanthanide Serisi boyunca değişebilir. Ancak, onların oxophilicity nedeniyle lantanit oksijen ve su ile kolayca tepki ve bu nedenle depolama, işleme, hazırlama ve harekete geçirmek için özel koşullar gerektirir. Bu faktörler organik sentez daha yaygın kullanımda sınırlıdır. Biz burada nasıl disprosiyum metal - ve kıyasen tüm lanthanide metaller - taze hazırlanmış torpidoda ve Schlenk teknikleri kullanarak susuz koşullar altında mevcut. Taze dosyalanmış metal alüminyum klorür ile birlikte seçici C-F harekete geçirmek trifluoromethylated benzofulvenes içinde başlatır. Sonuçta ortaya çıkan tepki ara ürün nitroalkenes ile difluoroalkenes yeni bir aile edinmek için tepki.

Nitroalkenes ile reaksiyonu ardından bu lanthanide-aracılı C-F etkinleştirme yordamı kolayca yeni difluoroalkenes nitro grubu içeren erişim sağlar. Makul tepki mekanizması Şekil 2' de tasvir edilir. Aldehitler electrophiles (Şekil 1)13kullanarak önceki çalışmalarımız aksine nitroalkenes 1,3-disubstituted inden ürünleri regioselectively satın almaya gücü yetmek. Bu nitroalkene grup bü...

Watch this Scientific Journal Video about Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes at JoVE.

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Bu iletişim kuralı elemental lantanit inert atmosfer altında hazırlanması ve bunların uygulama trifluoromethylated benzofulvenes içeren seçmeli bir C-F etkinleştirme işlemini açıklar.

Trifluoromethylated Benzofulvenes için çeşitli Difluoroalkenes erişim sağlayan Seçici C-F aktivasyonu Elemental lantanit uygulanması

The selective activation of one carbon-fluorine bond in polyfluorinated aromatic molecules or in trifluoromethyl-containing substrates offers the ...

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Chemistry

6.4K Görüntüleme.  Université de Reims Champagne Ardenne. Bu iletişim kuralı elemental lantanit inert atmosfer altında hazırlanması ve bunların uygulama trifluoromethylated benzofulvenes içeren seçmeli bir C-F etkinleştirme işlemini açıklar.

Video: Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes

The procedures described in this article involve the synthesis and isolation of hypervalent iodonium alkynyl triflates (HIATs) and their subsequent reactions with azides to form cyanocarbene intermediates. The synthesis of hypervalent iodonium alkynyl triflates can be facile, but difficulties stem from their isolation and reactivity. In particular, the necessity to use filtration under inert atmosphere at -45 &deg;C for some HIATs requires special care and equipment. Once isolated, the compounds can be stored and used in reactions with azides to form cyanocarbene intermediates. 
The evidence for cyanocarbene generation is shown by visible extrusion of dinitrogen as well as the characterization of products that occur from O-H insertion, sulfoxide complexation, and cyclopropanation. A side reaction of the cyanocarbene formation is the generation of a vinylidene-carbene and the conditions to control this process are discussed. There is also potential to form a hypervalent iodonium alkenyl triflate and the means of isolation and control of its generation are provided. The O-H insertion reaction involves using a HIAT, sodium azide or tetrabutylammonium azide, and methanol as solvent/substrate. The sulfoxide complexation reaction uses a HIAT, sodium azide or tetrabutylammonium azide, and dimethyl sulfoxide as solvent. The cyclopropanations can be performed with or without the use of solvent. The azide source must be tetrabutylammonium azide and the substrate shown is styrene.

Herein is described the synthesis, isolation, and reactions of hypervalent iodonium alkynyl triflates (HIATs) with azides to generate cyanocarbenes. The procedures will involve air-sensitive and cryogen techniques, including cold filtration under an inert atmosphere. Handling and safety of the synthesized compounds will also be discussed.

Yaratma Cyanocarbenes Uygulanması için hipervalent iyodonyum Alkınıl triflatların Sentezi

The procedures described in this article involve the synthesis and isolation of hypervalent iodonium alkynyl triflates (HIATs) and their subsequent ...

Kimya

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts

Ynones are a valuable functional group and building block in organic synthesis. Ynones serve as a precursor to many important organic functional groups and scaffolds. Traditional methods for the preparation of ynones are associated with drawbacks including harsh conditions, multiple purification steps, and the presence of unwanted byproducts. An alternative method for the straightforward preparation of ynones from acyl chlorides and potassium alkynyltrifluoroborate salts is described herein. The adoption of organotrifluoroborate salts as an alternative to organometallic reagents for the formation of new carbon-carbon bonds has a number of advantages. Potassium organotrifluoroborate salts are shelf stable, have good functional group tolerance, low toxicity, and a wide variety are straightforward to prepare. The title reaction proceeds rapidly at ambient temperature in the presence of a Lewis acid without the exclusion of air and moisture. Fair to excellent yields may be obtained via reaction of various aryl and alkyl acid chlorides with alkynyltrifluoroborate salts in the presence of boron trichloride.

The goal of this manuscript is to demonstrate a straightforward method for the preparation of ynones from acyl chloride and potassium alkynyltrifluoroborate salt starting materials. The one-pot reaction proceeds rapidly in the presence of boron trichloride without exclusion of air and moisture.

Asil klorür ve potasyum Alkynyltrifluoroborate Tuzlarından Ynones Metal içermeyen sentezi

Ynones are a valuable functional group and building block in organic synthesis. Ynones serve as a precursor to many important organic functional groups ...

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

Molecules bearing trifluoromethoxy (OCF3) group often show desired pharmacological and biological properties. However, facile synthesis of trifluoromethoxylated aromatic compounds remains a formidable challenge in organic synthesis. Conventional approaches often suffer from poor substrate scope, or require use of highly toxic, difficult-to-handle, and/or thermally labile reagents. Herein, we report a user-friendly protocol for the synthesis of methyl 4-acetamido-3-(trifluoromethoxy)benzoate using 1-trifluoromethyl-1,2-benziodoxol-3(1H)-one (Togni reagent II). Treating methyl 4-(N-hydroxyacetamido)benzoate (1a) with Togni reagent II in the presence of a catalytic amount of cesium carbonate (Cs2CO3) in chloroform at RT afforded methyl 4-(N-(trifluoromethoxy)acetamido)benzoate (2a). This intermediate was then converted to the final product methyl 4-acetamido-3-(trifluoromethoxy)benzoate (3a) in nitromethane at 120 &#176;C. This procedure is general and can be applied to the synthesis of a broad spectrum of ortho-trifluoromethoxylated aniline derivatives, which could serve as useful synthetic building blocks for the discovery and development of new pharmaceuticals, agrochemicals, and functional materials.

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

An operationally simple procedure for the synthesis of ortho-trifluoromethoxylated aniline derivatives via a two-step sequence of O-trifluoromethylation of N-aryl-N-hydroxyacetamide followed by thermally induced intramolecular OCF3-migration is reported.

Sentezi İçin Protokol<em&gt; Ortho</em&gt; -trifluoromethoxylated Anilin türevleri

Molecules bearing trifluoromethoxy (OCF3) group often show desired pharmacological and biological properties. However, facile synthesis of ...

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene

A reliable, intermediate scale preparation of 1,2,3,4,5-pentamethylcyclopentadiene (Cp*H) is presented, based on modifications of existing protocols that derive from initial 2-bromo-2-butene lithiation followed by acid mediated dienol cyclization. The revised synthesis and purification of the ligand avoids the use of mechanical stirring while still permitting access to significant quantities (39 g) of Cp*H in good yield (58%). The procedure offers other additional benefits, including a more controlled quench of excess lithium during the production of the intermediate heptadienols and a simplified isolation of Cp*H of sufficient purity for metallation with transition metals. The ligand was subsequently used to synthesize [Cp*MCl2]2 complexes of both iridium and ruthenium to demonstrate the utility of the Cp*H prepared and purified by our method. The procedure outlined herein affords substantial quantities of a ubiquitous ancillary ligand support used in organometallic chemistry while minimizing the need for specialized laboratory equipment, thus providing a simpler and more accessible entry point into the chemistry of 1,2,3,4,5-pentamethylcyclopentadiene.

Reliable, intermediate scale preparation of 1,2,3,4,5-pentamethylcyclopentadiene (Cp*H) is presented. The revised protocol for the synthesis and purification of the ligand minimizes the need for specialized laboratory equipment while simplifying reaction workups and product purification. Use of Cp*H in the synthesis of [Cp*MCl2]2 complexes (M = Ru, Ir) is also described.

Değerli Ligand Erişme Geçiş Metaller için altlıklar: 1,2,3,4,5-Pentamethylcyclopentadiene bir Modifiye, Ara Ölçeği Hazırlık

A reliable, intermediate scale preparation of 1,2,3,4,5-pentamethylcyclopentadiene (Cp*H) is presented, based on modifications of existing protocols that ...

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Direct cross-coupling between two alkenes via vinylic C-H bond activation represents an efficient strategy for the synthesis of butadienes with high atomic and step economy. However, this functionality-directed cross-coupling reaction has not been developed, as there are still limited directing groups in practical use. In particular, a stoichiometric amount of oxidant is usually required, producing a large amount of waste. Due to our interest in novel 1,3-butadiene synthesis, we describe the ruthenium-catalyzed olefination of electron-deficient alkenes using allyl acetate and without external oxidant. The reaction of 2-phenyl acrylamide and allyl acetate was chosen as a model reaction, and the desired diene product was obtained in 80% isolated yield with good stereoselectivity (Z,E/Z,Z = 88:12) under optimal conditions: [Ru(p-cymene) Cl2]2 (3 mol %) and AgSbF6 (20 mol %) in DCE at 110 &#186;C for 16 h. With the optimized catalytic conditions in hand, representative &#945;- and/or &#946;-substituted acrylamides were investigated, and all reacted smoothly, regardless of aliphatic or aromatic groups. Also, differently N-substituted acrylamides have proven to be good substrates. Moreover, we examined the reactivity of different allyl derivatives, suggesting that the chelation of acetate oxygen to the metal is crucial for the catalytic process. Deuterium-labeled experiments were also conducted to investigate the reaction mechanism. Only Z-selective H/D exchanges on acrylamide were observed, indicating a reversible cyclometalation event. In addition, a kinetic isotope effect (KIE) of 3.2 was observed in the intermolecular isotopic study, suggesting that the olefinic C-H metalation step is probably involved in the rate-determining step.

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

The ruthenium-catalyzed olefination of electron-deficient alkenes with allyl acetate is described here. By using aminocarbonyl as a directing group, this external oxidant-free protocol has high efficiency and good stereo- and regioselectivity, opening a novel synthetic route to (Z,E)-butadiene skeletons.

Kolay Hazırlık (2<em&gt; Z</em&gt; 4<em&gt; E</em&gt;) - Alil Asetat ile Elektronuz Alkenlerin Olefinasyonu ile Dienamidler

Direct cross-coupling between two alkenes via vinylic C-H bond activation represents an efficient strategy for the synthesis of butadienes with high ...

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Decomposition of N-tosyl-1,2,3-triazoles with rhodium(II) acetate dimer in the presence of alcohols forms synthetically versatile N-(2-alkoxyvinyl)sulfonamides, which react under a variety of conditions to afford useful N- and O-containing compounds. Acid-catalyzed addition of alcohols or thiols to N-(2-alkoxyvinyl)sulfonamide-containing phthalans provides access to ketals and thioketals, respectively. Selective reduction of the vinyl group in N-(2-alkoxyvinyl)sulfonamide-containing phthalans via hydrogenation yields the corresponding phthalan in good yield, whereas reduction with sodium bis(2-methoxyethoxy)aluminumhydride generates a ring-opened phenethylamine analogue. Because the N-(2-alkoxyvinyl)sulfonamide functional group is synthetically versatile, but often hydrolytically unstable, this protocol emphasizes key techniques in preparing, handling, and reacting these pivotal substrates in several useful transformations.

Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Representative experimental procedures for the synthesis of N-(2-alkoxyvinyl)sulfonamides and subsequent conversion to phthalan and phenethylamine derivatives are presented in detail.

Nhazırlanması-(2-alkoxyvinyl) N- tosyl-1,2,3-triazoles ve yerine Phthalans ve fenitilaminler sonraki dönüşüm sülfonamidler

Decomposition of N-tosyl-1,2,3-triazoles with rhodium(II) acetate dimer in the presence of alcohols forms synthetically versatile ...

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

&#945;-Functionalization of ketones via umpolung of enolates by hypervalent iodine reagents is an important concept in synthetic organic chemistry. Recently, we have developed a two-step strategy for ketone enolate umpolung that has enabled the development of methods for chlorination, azidation, and amination using azoles. In addition, we have developed C-C bond&#8211;forming arylation and allylation reactions. At the heart of these methods is the preparation of the intermediate and highly reactive enolonium species prior to addition of a reactive nucleophile. This strategy is thus reminiscent of the preparation and use of metal enolates in classical synthetic chemistry. This strategy allows the use of nucleophiles that would otherwise be incompatible with the strongly oxidizing hypervalent iodine reagents. In this paper we present a detailed protocol for chlorination, azidation, N-heteroarylation, arylation, and allylation. The products include motifs prevalent in medicinally active products. This article will greatly assist others in using these methods.

A two step one-pot protocol for the umpolung of ketone enolates to enolonium species and addition of a nucleophile to the &#945;-position is described. Nucleophiles include chloride, azide, azoles, allyl-silanes, and aromatic compounds.

Ketonlar ile Enolonium türler Umpolung Functionalization için bir iki adım iletişim kuralı

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

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes

We present the chemoselective synthesis of 1-(iodoethynyl)-4-methylbenzene, 1-(1,2-diiodovinyl)-4-methylbenzene, and 1-methyl-4-(1,2,2-triiodovinyl)benzene as representative examples for the practical chemoselective preparation of 1-iodoalkynes, 1,2-diiodoalkenes, and 1,1,2-triiodoalkenes from the chemoselective iodination of terminal alkynes mediated by hypervalent-iodine reagents. The chemoselectivity was confirmed by using p-tolylethyne as a model substrate to screen a variety of iodine sources and/or the hypervalent-iodine reagents. A combination of tetrabutylammonium iodide (TBAI) and (diacetoxyiodo)benzene (PIDA) selectively generates 1-iodoalkynes, while a combination of KI and PIDA generates 1,2-diiodoalkenes. A one-pot synthesis based on both TBAI-PIDA and KI-PIDA yields the corresponding 1,1,2-triiodoalkenes. These protocols were subsequently applied to the synthesis of synthetically important aromatic and aliphatic 1-iodoalkynes, 1,2-diiodoalkenes, and 1,1,2-triiodoalkenes, which were obtained in good yield with excellent chemoselectivity.

Herein, detailed protocols for the oxidative iodination of terminal alkynes using hypervalent-iodine reagents are presented, which chemoselectively afford 1-iodoalkynes, 1,2-diiodoalkenes, and 1,1,2-triiodoalkenes.

1-Iodoalkynes, 1,2-Diiodoalkenes ve 1,1,2-Triiodoalkenes Terminal Alkynes oksidatif iyodinasyon üzerinde dayalı Chemoselective hazırlanması

We present the chemoselective synthesis of 1-(iodoethynyl)-4-methylbenzene, 1-(1,2-diiodovinyl)-4-methylbenzene, and ...

Easy Access to Aliphatic Sulfonamides using Sulfamoyl Chlorides Under Visible Light Activation

Sulfonamides are prevalent motifs in marketed drugs and natural products. Their synthesis represents a great interest to the pharmaceutical industry, due to their unique biological properties. Recently, several methods for the synthesis of aryl sulfonamides have been developed, but little effort has focused on developing one-step methodologies to access sulfonamides flanked by two alkyl groups. This protocol describes a practical and facile method for the net hydrosulfamoylation of electron-deficient alkenes using sulfamoyl chlorides as radical precursors under blue-light activation. This practical and cost-effective methodology is performed in the presence of the metal-free photocatalyst Eosin Y and uses light as a clean and traceless energy source. The procedure is scalable, displays a broad functional group tolerance, and can be applied for late-stage functionalization. All reagents used in this protocol are commercially available. Simple reaction set-up, the absence of work-up and easy purification, demonstrate the convenience of this protocol. The reaction is best applied to electron-deficient alkenes.

<meta charset="utf8"></head><body>Görünür Işık Aktivasyonu Altında Sülfamoyl Klorürler Kullanılarak Alifatik Sülfonamidlere Kolay Erişim

Presented here is a protocol for the easy synthesis of aliphatic sulfonamides using sulfamoyl chlorides, (TMS)3SiH and Eosin Y under blue-light irradiation.

Görünür Işık Aktivasyonu Altında Sülfamoyl Klorürler Kullanılarak Alifatik Sülfonamidlere Kolay Erişim

Sulfonamides are prevalent motifs in marketed drugs and natural products. Their synthesis represents a great interest to the pharmaceutical industry, due ...

Trifluoromethylated Benzofulvenes için çeşitli Difluoroalkenes erişim sağlayan Seçici C-F aktivasyonu Elemental lantanit uygulanması

Özet

Daha Fazla Video Keşfet

Yaratma Cyanocarbenes Uygulanması için hipervalent iyodonyum Alkınıl triflatların Sentezi

Asil klorür ve potasyum Alkynyltrifluoroborate Tuzlarından Ynones Metal içermeyen sentezi

Sentezi İçin Protokol

Değerli Ligand Erişme Geçiş Metaller için altlıklar: 1,2,3,4,5-Pentamethylcyclopentadiene bir Modifiye, Ara Ölçeği Hazırlık

Kolay Hazırlık (2

Nhazırlanması-(2-alkoxyvinyl) N- tosyl-1,2,3-triazoles ve yerine Phthalans ve fenitilaminler sonraki dönüşüm sülfonamidler

Ketonlar ile Enolonium türler Umpolung Functionalization için bir iki adım iletişim kuralı

1-Iodoalkynes, 1,2-Diiodoalkenes ve 1,1,2-Triiodoalkenes Terminal Alkynes oksidatif iyodinasyon üzerinde dayalı Chemoselective hazırlanması

Görünür Işık Aktivasyonu Altında Sülfamoyl Klorürler Kullanılarak Alifatik Sülfonamidlere Kolay Erişim

Görünür Işık Aktivasyonu Altında Sülfamoyl Klorürler Kullanılarak Alifatik Sülfonamidlere Kolay Erişim