Asymmetric acetate aldol reactions in connection with an enantioselective total synthesis of macrolactin A
摘要:
Asymmetric aldol-like reactions of cinnamaldehyde, dienal 3 (fragment C7-C12 of macrolactin A), and dienal 4 (fragment C15-C24) with (i) chiral acetylthiazolidinethione-derived enolates, (ii) chiral boron enolates, and (iii) silyl enolates in the presence of chiral titanium-2,2'-dinaphthol complexes are compared. Use of the thiazolidinethione auxiliary and TiCl4 shows practical advantages; e.g., C5-C12 fragment 7 has been isolated enantiomerically pure in 74% yield. Copyright (C) 1996 Elsevier Science Ltd
A convenient stereoselective synthesis of conjugated (2Z)-EN-4-ynoic and (2Z,4Z)- and (2Z,4E)-dienoic acid derivatives from propiolic acid derivatives
作者:Xiyan Lu、Xiaoling Huang、Shengming Ma
DOI:10.1016/s0040-4039(00)92235-4
日期:1992.4
The palladium-catalyzed one-pot sequential reaction of propiolic acidderivatives with lithium halides first, and then with terminal alkynes or alkenes affords conjugated (2Z) -en-4-ynoic and (2Z,4Z)- and (2Z,4E)- dienoic acidderivatives with high stereoselectivity.
Chloroperoxidase-catalyzed oxidation of conjugated dienoic esters
作者:Despina J Bougioukou、Ioulia Smonou
DOI:10.1016/s0040-4039(01)02127-x
日期:2002.1
The chloroperoxidase (CPO)-catalyzed oxidations of dienes conjugated to an ester group were studied using tert-butyl hydroperoxide as the terminal oxidant. (C) 2002 Elsevier Science Ltd. All rights reserved.
Asymmetric acetate aldol reactions in connection with an enantioselective total synthesis of macrolactin A
Asymmetric aldol-like reactions of cinnamaldehyde, dienal 3 (fragment C7-C12 of macrolactin A), and dienal 4 (fragment C15-C24) with (i) chiral acetylthiazolidinethione-derived enolates, (ii) chiral boron enolates, and (iii) silyl enolates in the presence of chiral titanium-2,2'-dinaphthol complexes are compared. Use of the thiazolidinethione auxiliary and TiCl4 shows practical advantages; e.g., C5-C12 fragment 7 has been isolated enantiomerically pure in 74% yield. Copyright (C) 1996 Elsevier Science Ltd