Piperidine → pyrrolidinyl-N-tert-butylcarbamate

Participants

Reaction Conditions

Reaction Steps

It is necessary to use a protecting group to prepare certain amines. A suitable protecting group is tert-butylcarbamate ("BOC") which was used to prepare 2-trimethylsilylpiperidine, 2-trimethylsilylpyrollidine, 2-(3-methylphenyl)piperidine, and a 2-(3-methylphenyl)pyrrolidine. The BOC group was attached by generating the anion from either piperidine or pyrrolidine using sodium hydride in tetrahydrofuran. This solution was cooled to 5° C. and a slight excess of di-tert-butyldicarbonate added. After two hours, the solution was poured into saturated sodium bicarbonate and the layers separated. The organic layer was dried over magnesium sulfate and the solvent removed by rotary evaporation. Distillation at reduced pressure provided either piperidinyl-N-tert-butylcarbamate (bp 95° C., 3 mm Hg, 89% yield) or pyrrolidinyl-N-tert-butylcarbamate (bp 69° C., 1 mm Hg, 95% yield).

Provenance & Evidence