Guanidine Bases in Synthesis: Extending the Scope of the Corey-Chaykovsky Epoxidation
作者:Andrew Graham、David Phillips
DOI:10.1055/s-0029-1219359
日期:2010.3
Guanidine bases, such as 1,5,7-triazabicyclo[4.4.0]dec-1-ene (TBD) or 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-1-ene (MTBD), are highly effective reagents for the in situ generation of sulfonium ylides from sulfonium salts in Corey-Chaykovsky epoxidation reactions of aldehydes. These reactions proceed rapidly to produce the corresponding epoxides in excellent yields and with high selectivity for the trans product. Significantly, this reagent combination is applicable to both nonenolizable and enolizable aldehydes and α,β-unsaturated aldehydes.
胍基化合物,如1,5,7-三氮杂双环[4.4.0]癸-1-烯(TBD)或7-甲基-1,5,7-三氮杂双环[4.4.0]癸-1-烯(MTBD),是有效的试剂,可在Corey-Chaykovsky环氧化反应中可以原位生成磺壳盐中的磺烯烃。这些反应迅速进行,生成相应的环氧化物,产率极高,并且对反式产物具有较高的选择性。值得注意的是,这种试剂组合适用于不可酯化和可酯化的醛以及α,β-不饱和醛。