Department of Chemistry, University of Science and Technology of China , Hefei, Anhui 230026, China.
J Org Chem. 2013 Nov 1;78(21):11071-5. doi: 10.1021/jo401736k. Epub 2013 Oct 16.
A range of ketone-stabilized phosphonium ylides were allylated with high regioselectivity by primary allylic amines in the presence of 5 mol % Pd(PPh3)4 and 10 mol % B(OH)3, and subsequent one-pot Wittig olefination gave structurally diverse α,β-unsaturated ketones in good to excellent overall yields with excellent E selectivity. The one-pot allylation/olefination reaction was extended to ester- and nitrile-stabilized phosphonium ylides by replacing B(OH)3 with TsOH, and the corresponding α,β-unsaturated esters and nitriles were obtained in moderate overall yields.
一系列酮稳定的鏻叶立德在 5 mol% Pd(PPh3)4 和 10 mol% B(OH)3 的存在下,与一级烯丙基胺高区域选择性地烯丙基化,随后一锅法 Wittig 烯烃化得到结构多样的α,β-不饱和酮,总收率好至优秀,E 选择性极好。通过用 TsOH 代替 B(OH)3,将一锅法的烯丙基化/烯烃化反应扩展到酯基和腈基稳定的鏻叶立德,得到了中等总收率的相应的α,β-不饱和酯和腈。