2-Methylpyrrolidine → 1-[2-(6-Bromo-naphthalen-2-yl)-ethyl]-2-methyl-pyrrolidine

Participants

Reaction Steps

2-Bromo-6-vinyl-naphthalene is treated with a 2-methylpyrrolidine anion generated with n-butyllithium to provide 1-[2-(6-bromo-naphthalen-2-yl)-ethyl]-2-methyl-pyrrolidine. Preferably, about 1.2 to about 2.5 molar equivalents of 2-methylpyrrolidine are used for the reaction. The reaction typically is accomplished in an organic solvent, for example, THF, methyl-t-butyl ether (MTBE), Et2O, and DME. The preferred solvent is tetrahydrofuran (THF). The n-butyllithium is added to a THF solution of 2-methylpyrrolidine in a controlled fashion, typically in a dropwise manner. To this solution is added a THF solution of 2-bromo-6-vinyl-naphthalene. Alternatively, it is also suitable to the THF solution of 2-bromo-6-vinyl-naphthalene to the solution of 2-methylpyrrolidine and n-butyllithium. The reaction is accomplished at below room temperature, typically in a temperature range from about 0° C. to about −20° C. From about 0.3 to about 0.7 molar equivalents of n-butyllithium are used relative to the 2-bromo-6-vinylnaphthalene compound. The resulting compound is 1-[2-(6-bromo-naphthalen-2-yl)-ethyl]-2-methyl-pyrrolidine.

Provenance & Evidence