(6-溴色烷-2-基)甲醇

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 297 parts of 6-bromo-3,4-dihydro-2H-1-benzopyran-2-methanol and 108 parts of copper (I) cyanide in 450 parts of N,N-dimethylformamide was stirred and refluxed for 4 hours. The reaction mixture was poured onto a solution of 600 parts of iron chloride in 180 parts of hydrochloric acid and 1000 parts of water. The whole was stirred for 20 minutes at 60° C. The aqueous phase was extracted with methylbenzene. The extract was filtered over Hyflo. The filtrate was washed successively with 10% hydrochloric acid, water, 10% sodium hydroxide and again with water, filtered again, dried and evaporated, yielding 112 parts (49.3%) of 3,4-dihydro-2-(hydroxymethyl)-2H-1-benzopyran-6-carbonitrile; mp. 85° C. (intermediate 2). refluxed for 4 hours The whole was stirred for 20 minutes at 60° C The aqueous phase was extracted with methylbenzene The extract was filtered over Hyflo The filtrate was washed successively with 10% hydrochloric acid, water, 10% sodium hydroxide and again with water filtered again dried evaporated

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a stirred mixture of 80 parts of 6-bromo-3,4-dihydro-2H-benzopyran-2-carboxylic acid and 225 parts of tetrahydrofuran were added dropwise 400 parts of a solution of borane, compound with thiobismethane 0.2N in tetrahydrofuran. Upon completion, stirring was continued for 4hours at room temperature. 80 parts of methanol were added dropwise and stirring was continued for 30 minutes at reflux temperature. The solvent was distilled off till half its volume. The remaining solvent was evaporated and the residue was distilled, yielding 63 parts (86%) of 6-bromo-3,4-dihydro-2H-1-benzopyran-2-methanol; bp. 150° C. at 39.9 Pa (intermediate 1). stirring was continued for 30 minutes at reflux temperature The solvent was distilled off till half its volume The remaining solvent was evaporated the residue was distilled