Synthesis of unsymmetrically 2,6-disubstituted 2,3-dihydrothiopyran-4-ones
摘要:
A series of 2,3-dihydrothiopyran-4-one derivatives with unequal substituents in the 2- and 6-position have been prepared by double conjugate addition of sulfide to enynones. These starting materials were accessed in two steps from terminal alkynes and alpha,beta-unsaturated aldehydes. (c) 2006 Elsevier Ltd. All rights reserved.
Synthesis of Unsymmetrically Substituted 1,3-Butadiynes and 1,3,5-Hexatriynes via Alkylidene Carbenoid Rearrangements
作者:Annabelle L. K. Shi Shun、Erin T. Chernick、Sara Eisler、Rik R. Tykwinski
DOI:10.1021/jo026481h
日期:2003.2.1
Unsymmetrically substituted 1,3-butadiynes and 1,3,5-hexatriynes are synthesized in four steps from commercially available aldehydes or carboxylic acids. The key step in this process involves a Fritsch-Buttenberg-Wiechell rearrangement, in which an alkylidene carbenoid intermediate subsequently rearranges to the desired polyyne. This rearrangement proceeds under mild conditions, and it is tolerant
Friedel-crafts reactions of bis(trimethylsilyl)polyynes with acyl chlorides; a useful route to terminal-alkynyl ketones
作者:D.R.M. Walton、F. Waugh
DOI:10.1016/s0022-328x(00)89260-8
日期:1972.4
chloride-aluminium chloride complexes, XC6H4 COCl·AlCl3 in methylene chloride at 0–20° to form the corresponding ketones XC6H4CO(CC)nSiMe3 in excellent (n = 1) or moderate (n = 2, 4) yield. Treatment of the products with aqueous methanolic borax results in virtually quantitative liberation of the terminal alkynyl ketones XC6H4CO(CC)nH. The method provides the first practical route to the ketotetraynes (n = 4) and
双(三甲基甲硅烷基)乙炔Me 3 Si(CC)n SiMe 3与酰氯-氯化铝络合物XC 6 H 4 COCl·AlCl 3在二氯甲烷中于0-20°反应形成相应的酮XC 6 H 4 CO(CC)n SiMe 3具有极好(n = 1)或中等(n = 2,4)的产率。用含水甲醇硼砂处理产品实际上可定量释放末端炔基酮XC 6 H 4 CO(CC)nH.该方法提供了通向酮四炔的第一种实用途径(n= 4),并有用地补充了现有的用于酮-单炔和-二炔合成的氧化方法。与我草酰氯氯化-铝复合发生反应3 SiCCSiMe 3,得到新的甲硅烷基取代的杂环(I):
Synthesis of 2-(Hetero)aryl-5-(trimethylsilylethynyl)oxazoles from (Hetero)arylacrylic Acids
作者:Alena S. Pankova、Alexander Yu. Stukalov、Mikhail A. Kuznetsov
DOI:10.1021/acs.orglett.5b00009
日期:2015.4.17
A three-step method for the synthesis of 2-(hetero)aryl-5-(trimethylsilylethynyl)oxazoles is described. Easily accessible bis(trimethylsilyl)acetylene and acrylic acid derivatives are used as starting materials for the preparation of mono- and disubstituted 5-(trimethylsilyl)pent-1-en-4-yn-3-ones. Oxidative phthalimidoaziridination of these enynones provides the key 2-acyl-1-phthalimidoaziridines that
作者:Erin Westley、Madison J. Sowden、Nicholas L. Magann、Kelsey L. Horvath、Kieran P. E. Connor、Michael S. Sherburn
DOI:10.1021/jacs.1c11598
日期:2022.1.19
A general synthetic approach to molecular structures that are hybrids of tetraethynylethylene (TEE) and tetravinylethylene (TVE) is reported. The synthesis permits the controlled preparation of many previously inaccessible structures, including examples with different substituents on each of the four branching arms. Most substituted TVE–TEE hybrids are found to be significantly more robust compounds