Practical synthesis of Z-unsaturated esters by using a new Horner-Emmons reagent, ethyl diphenylphosphonoacetate
作者:Kaori Ando
DOI:10.1016/0040-4039(95)00726-s
日期:1995.6
A new Horner-Emmons reagent, ethyl diphenylphosphonoacetate 1 was prepared from triethyl phosphonoacetate, PCl5, and phenol in 60% overall yield. Horner-Emmons reactions of 1 with aldehydes in the presence of Triton® B or NaH in THF gave the Z-unsaturated esters in 89–93% selectivity in almost quantitative yields. Furthermore, 1 showed up to 99% Z-selectivity under Still's condition (KHMDS/18-crown-6)
由膦酸三乙酯,PCl 5和苯酚制备了一种新的Horner-Emmons试剂二苯基膦酸乙酯1,总收率为60%。的霍纳-埃蒙斯反应1与曲通的存在醛®,在THF乙或NaH得到Ž以几乎定量的产率不饱和酯在89-93%的选择性。此外,在斯蒂尔条件下(KHMDS / 18-crown-6),1表现出高达99%的Z选择性。