反应详情

In a still different procedure (Reaction Scheme E below), in which the order of steps is somewhat changed, the methyl dl-2-benzyloxy-6-azido-5,6,7,8-tetrahydro-1-naphthoate (XXV) can be treated with ammonia in methanol under pressure to yield the corresponding dl-2-benzyloxy-6-azido-5,6,7,8-tetrahydronaphthalene-1-carboxamide (XXXIX). Conversion of the azide group to an amino group with hydrazine and Raney nickel yields a dl-2-benzyloxy-6-amino-5,6,7,8-tetrahydronaphthalene-1-carboxamide (XXXXI). This compound can be treated directly with hydrogen in the presence of a palladium catalyst to remove the benzyl group and yield a compound according to formula Ib above wherein R2 and R3 are both hydrogen. Alternatively, the benzyloxy derivative can be alkylated with a lower aldehyde and sodium cyanoborohydride to yield a dl-2-benzyloxy-6-dialkylamino-5,6,7,8-tetrahydronaphthalene-1-carboxamide (XXXXI) which compound, upon treatment with hydrogen in the presence of a palladium catalyst, yields a compound of this invention (Ib) where R2 and R3 are individually Me, Et or n-Pr.

1. customIn a still different procedure (Reaction Scheme E below)