在 Sharpless 的 AD mix-β™ 存在下,α,β-不饱和酮的不对称二羟基化产生 α,β-二羟基酮,如果存在苯基硼酸,则生成相应的苯基硼酸酯。这些物种的 C α -O 键在 -78 °C 下被去除 - 在前一种情况下是在丙酮化物形成后,在后一种情况下直接 - 以前所未有的方式,即通过用 Sm II 溴化物在 THF/MeOH 中的悬浮液处理. 如果需要,可以还原所得的单羟基酮以得到顺式或反式构型的 1,3-二醇。在 0 °C 下用 Sm II 溴化物一锅还原 α,β-二羟基酮双丙酮化物,产生相同的二醇。当同样处理α,β-二羟基酮苯基硼酸酯时,得到1,3-二醇的苯基硼酸酯。
An efficient synthesis of (E)-α,β-unsaturated ketones and esters with total stereoselectivity by using chromium dichloride
作者:José M. Concellón、Humberto Rodríguez-Solla、Carmen Méjica
DOI:10.1016/j.tet.2006.01.052
日期:2006.4
(E)-α,β-Unsaturatedketones 1 or esters 2 can be obtained with complete stereoselectivity by reaction of different 2-chloro-3-hydroxy ketones 3 or esters 4 and CrCl2. A comparative study of the results of synthesis of ketones 1 with CrCl2 or samarium is performed. A mechanism to explain both β-elimination reactions has been proposed.
Carbonyl transposition on organoselenium compounds
作者:João V. Comasseto、Wai L. Lo、Nicola Petragnani
DOI:10.1016/s0040-4020(97)00454-7
日期:1997.6
Carbonyl conjugated vinylic selenides undergo 1,3 and 1,5-carbonyl transposition sequences through organometallic reagents addition reactions followed by acid hydrolysis.
β-Phenylseone α,β-Unsaturated Aldehydes, Efficient Three Carbon Homologating Agents. 1,3-Carbonyl Transposition
作者:Elena P. Arrua、João V. Comasseto
DOI:10.1080/00397919108021067
日期:1991.8
Abstract The easily obtained β-phenylseleno α,β-unsaturated aldehydes react with Grignardreagents and with n-butyllithium leading to the 1,2-addition products, which upon acidic hydrolysis in the presence of silica gel afford the selenium-free α,β-unsaturated carbonyl compounds with 1,3-carbonyl transposition.
Kumulierte Ylide XIX.<sup>1</sup>Acylphosphoniumylide durch kettenverlängernde Difunktionalisierung von Grignard-Verbindungen mit Ketenylidentriphenylphosphoran. Anwendung zur Synthese (<i>E</i>)-α,β-ungesättigter-Ketone und der Königinsubstanz
作者:Hans Jürgen Bestmann、Martin Schmidt、Rainer Schobert
DOI:10.1055/s-1988-27461
日期:——
Cumulated Ylides XIX.1 Chain-lengthening Difunctionalization of Grignard Compounds by Reaction with Ketenylidenetriphenylphosphorane. A New Route to (E)-α,β- Unsatured Ketones and the Queen Substance2 The reaction of Grignard compounds with ketenylidenetriphenylphosphorane and subsequent hydrolysis yields 2-oxoalkylidenetriphenylphosphoranes. The latter undergo Wittig reaction, whereby (E-α,β-unsaturated ketones are obtained. An application of this strategy to the synthesis of carbonyl homologues of Lepidoptera pheromones and the queen substance is shown.