acrylic acid (R)-1-{(4R,5R)-2,2-dimethyl-5-phenyl[1,3]dioxolan-4-yl}-2,2-difluorobut-3-enyl ester 在
RuCl2(1,3-dimesityl-imidazolidin-2-yl)(PCy3)(=CHPh) titanium(IV) isopropylate 作用下,
以
甲苯 为溶剂,
反应 3.5h,
以62%的产率得到(R)-6-{(4S,5R)-2,2-dimethyl-5-phenyl[1,3]dioxolan-4-yl}-5,5-difluoro-5,6-dihydropyran-2-one