Regio- and Diastereocontrol in Carbonyl Allylation by 1-Halobut-2-enes with Tin(II) Halides
作者:Akihiro Ito、Masayuki Kishida、Yasuhiko Kurusu、Yoshiro Masuyama
DOI:10.1021/jo991403o
日期:2000.1.1
diastereoselective. The allylation of benzaldehyde by 1-chlorobut-2-ene in 1,3-dimethylimidazolidin-2-one (DMI) does not occur with tin(II) chloride or bromide but does proceed with tin(II) iodide and exhibits gamma-syn selectivity which is unusual for a Barbier-type carbonyl allylation. In the carbonyl allylation by 1-chlorobut-2-ene with any tin(II) halide, the addition of tetrabutylammonium iodide (TBAI) accelerates
描述了1-卤代丁-2-烯与卤化锡(II)的区域和非对映选择性羰基烯丙基化。二氯甲烷-水双相体系中的溴化锡(II)是一种有效的试剂,可用于1-溴丁-2-烯的不寻常的α-区域选择性羰基烯丙基化反应,以生成1-取代的pent-3-en-1-ols。将四丁基溴化铵(TBABr)加到双相体系中,可通过通常的γ加成反应生成1-取代的2-甲基丁-3-en-1-醇,这与没有TBABr的α加成相反。与芳族醛的γ加成表现出反非对映选择性,而对脂族醛的γ不是非对映选择性。1-氯丁-2-烯在1中苯甲醛的烯丙基化 3-二甲基咪唑啉-2-酮(DMI)不会与氯化锡(II)或溴化物一起出现,但会与碘化锡(II)一起出现,并表现出γ-syn选择性,这对于Barbier型羰基烯丙基化反应是不寻常的。在1-氯丁-2-烯与任何卤化锡(II)进行的羰基烯丙基化反应中,加入四丁基碘化铵(TBAI)可以加快反应速度,并提高γ-syn的