Efficient Synthesis of
α
‐Benzylidene‐
γ
‐methyl‐
γ
‐butyrolactones
摘要:
A concise synthesis of alpha-benzylidene-gamma-methyl-gamma-butylolactones 5a-g from substituted benzaldehydes is described. Compounds la-g on reaction with phosphorane 2, provide the pentenoates 3a-g, which can be hydrolyzed to the acids 4a-g. The latter are cyclized to the corresponding butyrolactones 5a-g in excellent yields. The pentenoates 3a-g, on acid catalyzed cyclization, also provide 5a-g in very high yields.
hydroacyloxylation of unactivated alkenes, offering a streamlined access to relevant γ-lactones, which features the utilization of either a calcium(II) salt or triflimide as a catalyst in hexafluoroisopropanol. This method could be applied to the synthesis of natural products and the late-stage functionalization of natural and bioactive molecules. Additionally, DFT computations were used to elucidate the twist