An Efficient Synthesis of Acetylenic γ- and δ-Hydroxy Ketones, γ- and δ-Keto Acids, and γ-Diketones via Addition of 1-Alkinyllithium Compounds to γ- and δ-Lactones

Article abstract of DOI:10.1002/prac.19933350503

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 γ-valerolactone (1a), γ-butyrolactone (1b) or