An efficient Synthesis of Acetylenic ?- and ?-Hydroxy Ketones, ?- and ?-keto acids, and ?- diketones via addition of 1-alkinyllithium compounds to ?- and ?-lactones
作者:Christine Wedler、Hans Schick
DOI:10.1002/prac.19933350503
日期:——
2-Hydroxy-6-alkyn-5-ones 3, 1-hydroxy-5-alkyn-4-ones 4, and 1-hydroxy-6-alkyn-5-ones 5 are conveniently obtained in exellent yields through a highly selective monoaddition of an 1-alkynyllithium compound 2 to gamma-valerolactone (1 a), gamma-butyrolactone (1 b) or delta-valerolactone (1 c). They are oxidized by pyridinium dichromate or Jones reagent to the corresponding acetylenic 1,4-diketones 6, 4-oxo carboxylic acids 7, and 5-oxo carboxylic acids 8, respectively.