Polarized ketene dithioacetals. 28. A new general highly stereoselective and regiospecific method for homologation of ketones to .alpha.,.beta.-unsaturated esters via .alpha.-oxoketene dithioacetals
New method for aziridination of olefinic esters is described.
新的烯丙基酯环氧胺化方法。
Formation of unsaturated esters in the single electron transfer reaction of cyclopropanone acetals with quinones under non-irradiated conditions
作者:Manabu Abe、Akira Oku
DOI:10.1016/s0040-4039(00)73235-7
日期:1994.5
Unsaturated esters were formed from cyclopropanone acetals in the reaction with DDQ or chloranil, where ring-opened CC and CO bonded adducts were the intermediates formed via a SET mechanism resulting in the ester formation.
Tetrasubstituted (Z)-alkenes were readily prepared through the Horner-Wadsworth-Emmons reactions of methyl 2-[bis(2,2,2-trifluoroethyl)phosphono]propionate with arylalkylketones by employing Sn(OSO(2)CF(3))(2) and N-ethylpiperidine.
Excellent Z or E selectivity is observed in the
HornerâWadsworthâEmmons reactions of methyl
bis(trifluoroethyl)phosphonoacetate 2 with aryl alkyl ketones 3aâd
or aldehydes 3f,g using Sn(OSO
2
CF
3
)
2
in
the presence of N-ethylpiperidine, which should have a different
reaction mode to those using sodium hydride.
Stereoselective Coupling Reaction of (2Z)-β-Arylselenocinnamic Esters with Grignard Reagents in Presence of CuI
作者:Xian Huang、Chang-Qiu Zhao
DOI:10.1080/00397919708007069
日期:1997.10.1
Abstract Stereoselective synthesis of trisubstituted alkenes linked with ester groups via coupling reaction of (2Z)-β-arylselenocinnamic esters with Grignardreagents in presence of equal molar quantities of CuI was reported.
摘要 报道了在等摩尔量的 CuI 存在下,通过 (2Z)-β-芳基硒肉桂酸酯与格氏试剂的偶联反应,立体选择性合成与酯基连接的三取代烯烃。