反应详情

(2R)-1,1-Diphenyl-2-Allyloxy-Pent-4-en 26b (0.25 g, 0.90 mmol) was cyclized in the presence of Grubb's catalyst (0.037 g, 0.045 mmol) (Procedure C) to produce (2R)-2-Benzhydryl-3,6-dihydro-2H-pyran 27b 0.2 g (89%, [α]D=(+)80.8, c=1, MeOH). The 1HNMR and 13CNMR were identical with (2S)-2-benzhydryl-3,6-dihydro-2H-pyran 27a.