[CH2:1]1[O:9][C:8]2[CH:7]=[CH:6][C:5]([CH2:10][CH2:11][CH:12]([C:14]3([CH3:17])[CH2:16][CH2:15]3)O)=[CH:4][C:3]=2[O:2]1.P(Br)(Br)[Br:19].[Br-].[Li+]>[Br-].[Zn+2].[Br-]>[CH3:17][C:14](=[CH:12][CH2:11][CH2:10][C:5]1[CH:6]=[CH:7][C:8]2[O:9][CH2:1][O:2][C:3]=2[CH:4]=1)[CH2:15][CH2:16][Br:19][V; Ar is 3,4-methylenedioxyphenyl, R is CH3 ] was prepared from 17.6 g. of 2-(3,4-methylenedioxyphenyl)ethyl 1-methylcyclopropyl carbinol (Preparation B3), 20.3 g. of phosphorus tribromide, 18.5 g. of lithium bromide and 21 g. of zinc bromide according to the procedure given above in Preparation C1, affording 19 g. of product as an oil.
Wird geladen…