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Diastereoselective enolate alkylation reactions of N-acylsulfinamides and conversion of the alkylation products to a variety of enantiopure products are reported. Several sulfinamides were prepared in solution followed by acylation to provide N-acylsulfinamides. The N-acylsulfinamides were then evaluated in diastereoselective enolate alkylation reactions. Of the sulfinamides evaluated, tert-butanesulfinamide provided the highest diastereoselectivity. To establish the potential utility of sulfinamides as versatile auxiliaries, methods were developed for (1) the racemization-free acylation of tert-butanesulfinamide to prepare optically pure N-acyl-tert-butanesulfinamides, (2) the diastereoselective C-alkylation of N-acyl-tert-butanesulfinamides, (3) the conversion of the N-acyl-tert-butanesulfinamides to the active ester equivalent by N-alkylation and S-oxidation, and (4) the cleavage of the N-alkyl-N-acyl-tert-butanesulfonamides to give chiral alcohol, ester, amide, and carboxylic acid target compounds. These studies provide the groundwork for the development of sulfinamides as dual chiral auxiliaries and linkers for the multistep solid-phase synthesis of enantioenriched compounds.

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The first demonstration of the rapid parallel synthesis of diverse prostaglandin derivatives is reported. Upper (alpha-) side chain diversity was introduced to core 1 via the parallel Suzuki coupling of hydroborated alkenes. Conversion to the enones 3 and 9 was followed by the addition of the lower (omega-) side chains as higher-order cuprates 4. Upper side chains incorporating an N-acylsulfonamide protecting group were further transformed into prostaglandin amide analogues. Cleavage from support with HF/pyridine followed by scavenging provided 26 prostaglandin E1 analogues in high purity.

Amines Amines Q 0120Parallel Solution-Phase Asymmetric Synthesis of α-Branched Amines. -A general method for parallel solution-phase asymmetric synthesis of the title compounds is developed. All work-up procedures are based on filtration to avoid any chromatography or crystallization. -(MUKADE, T.; DRAGOLI, D. R.; ELLMAN*, J. A.; J. Comb. Chem. 5 (2003) 5, 590-596; Cent. New Direct. Org. Synth., Dep. Chem., Univ. Calif., Berkeley, CA 94720, USA; Eng.) -Nuesgen 06-067