1,5-Dibromopentane → HCID 14329717, compound
Reaction equation
[CH3:1][O:2][C:3]([C@:5]1([CH3:19])[CH2:10][CH2:9][C:8]2[C:11]([CH3:18])=[C:12]([OH:17])[C:13]([CH3:16])=[C:14]([CH3:15])[C:7]=2[O:6]1)=[O:4].[Br:20][CH2:21][CH2:22][CH2:23][CH2:24][CH2:25]Br>C(Cl)(Cl)Cl>[CH3:1][O:2][C:3]([C@:5]1([CH3:19])[CH2:10][CH2:9][C:8]2[C:11]([CH3:18])=[C:12]([O:17][CH2:25][CH2:24][CH2:23][CH2:22][CH2:21][Br:20])[C:13]([CH3:16])=[C:14]([CH3:15])[C:7]=2[O:6]1)=[O:4]Participants
4
Procedure
Using the procedure and molar proportions of example 71, (S)-(-)-6-hydroxy-3,4-dihydro-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carboxylic acid methyl ester was alkylated with 1,5-dibromopentane giving (S)-(-)-6-[(5-bromopentyl)oxy]-3,4-dihydro-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carboxylic acid methyl ester, [α]D25 -35.60° (c2, CHCl3), in 88.5% yield.