2,4,6-Trimethylpyridine → (R)-3-Carboxy-N,N,N-trimethyl-2-{[hydroxy(tetradecyloxy)phosphinyl]oxy}-1-propanaminium Hydroxide

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Reaction Steps

To a solution of 16.4 gm of the tetrafluoroborate salt of L-carnitine and 26 gm of collidine in 263 ml of acetonitrile is added 29.4 gm of dichlorotetradecylphosphite. The reaction mixture is stirred at room temperature for 17 hours and then a solution of 21.1 gm of sodium metaperiodate in 48.7 ml of water is added. After stirring at room temperature for two hours, the reaction mixture is filtered through Celite and the filtrate is concentrated under vacuum. The residue is flash chromatographed on normal phase silica gel, initially with a 50/30/3 ratio of chloroform/methanol/concentrated ammonium hydroxide and then with a 50/30/10 ratio of the same solvent system to yield a product that is then flash chromatographed on LiChroprep RP-8 silica gel using gradients from water to acetonitrile and to methanol. The title compound is isolated as an amorphous solid, (m.p. ~190° C. [dec]; 31P NMR=0.324 ppm; [α]25 =-10.34 C=1.0 MeOH).

Provenance & Evidence