Development of a Chemoenzymatic Route to (R)-Allyl-(3-amino-2-(2-methylbenzyl)propyl)carbamate

A chemoenzymatic route to (R)-allyl-(3-amino-2-(2-methylbenzyl)propyl)carbamate (1-(R)) has been developed on a kilogram scale. The key intermediate, 2-(2-methylbenzyl)propane-1,3-diamine 4, was isolated as a tartrate salt in a three-step sequence starting from 2-methylbenzyl chloride. The subsequent lipase-catalyzed desymmetrization was optimized, and 1-(R) was isolated as the d-tartrate salt.