Entrainment resolution of carnitinamide chloride

The ready availability of (R)-carnitinamide, an immediate synthetic precursor of (R)-carnitine, is an ambitious goal and resolutions, due to the very low cost of racemic carnitinamide, can be the most convenient stereotechnology to reach it. We have efficiently resolved carnitinamide chloride by preferential crystallization from methanol according to simple entrainment procedure. The previous transformation of the chloride into other salts or the use of specific solvent systems was not required for successful resolution, as in the case of the reported entrainment of carnitinamide precursor, carnitine nitrile.