Propanediol 1-phenyl-, diacetate

The 5 -(-)-2-cyclohexy 1-1,3-propanediol monoacetate (24) and the S-( )-2-phenyl-1,3-propanediol monoacetate (25) are key chiral intermediates for the chemoenzymatic synthesis of Monopril (26) (Fig. 10), a new antihypertensive drug which acts as an ACE inhibitor. The asymmetric hydrolysis of 2-cyclohexyl-1,3-propanediol diacetate (27) and 2-phenyl-1,3-propanediol diacetate (28) to the corresponding S-( - )-monoacetate (24) and S-( )-monoacetate (25) by porcine pancreatic lipase (PPL) and Chromobacterium viscosum lipase have been demon-... 

Figure 10 Preparation of chiral synthon for monopril asymmetric enzymatic hydrolysis of 2-cyclohexyl- and 2-phenyl-1,3-propanediol diacetate (27) and (28) to the corresponding S-(—)-monoacetates.

RN Patel, RS Robison, LJ Szarka. Stereoselective enzymic hydrolysis of 2-cyclo-hexyl- and 2-phenyl-1,3-propanediol diacetate in biphasic systems. Appl Microbiol Biotechnol 34 10-14, 1990. 

Allylbenzene added to ethereal butyllithium, allowed to stand overnight at room temp., added dropwise to an ice-cooled 2 M soln. of borane in tetrahydrofuran, stirred 5 hrs., treated in turn with water, 3 N NaOH, and HgOg, the resulting crude l-phenyl-l,3-propanediol allowed to react overnight with 1 1 acetic anhydride-pyridine 1-phenyl-1,3-propanediol diacetate. Y 65%. F. e. s. J. Klein and A. 

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