Synthesis of a Chiral 3, 3′-Di-tert-butyl-2, 2′-bipyrrole

P Skowronek, DA Lightner

Index: Skowronek, Pawel; Lightner, David A. Monatshefte fur Chemie, 2003 , vol. 134, # 6 p. 889 - 899

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Citation Number: 19

Abstract

Summary. Diethyl 3, 3′-di-tert-butyl-4, 4′-dimethyl-2, 2′-bipyrrole-5, 5′-dicarboxylate was synthesized in four steps from ethyl 3, 5-dimethyl-1 H-pyrrole-2-carboxylate. The CH 2 hydrogens of the ethyl ester groups of the former are diastereotopic in the 1 H-NMR, consistent with axial chirality of the bipyrrole and restricted rotation about the 2, 2′-bipyrrole bond, due to the tert-butyl groups. An X-ray structure of the crystalline target compound ...