Propranolol, chiral synthesis

Aigbirhio, F., Pike, V.W., Francotte, E., Waters, S.L., Banfield, B., Jaeggi, K.A., Drake, A., 1992. 5-[l-(2,3-Diaminophenoxy)]-3 -(A -t-butylamino)propan-2 -ol simplified asymmetric synthesis with CD and chiral HPLC analysis. Tetrahedron Asymmetry 3, 539-554. Antoni, G., Ulin, J., Langstrom, B., 1989. Synthesis of the "C-labelled p-adrenergic receptor ligands atenolol, metoprolol and propranolol. Appl. Radial. Isot. 7, 561-564. 

The seminal enantioselective allylic alcohols epoxidation realized by Katsuki and Sharpless [18] to which other similarly steroselective reactions soon followed (e.g., bishydroxyla-tion, cyclopropanation, lactonization and catalytic hydrogenation) have been invaluable for this purpose. One of the most significant applications, as far as drug synthesis is concerned, of the Sharpless method from the innumerable ones which have been found in the past 20 years is the routine preparation (Fig. 6) of antipodal pairs of known chirality of (3-blockers such as propranolol (5) [19]. 

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