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Updated: Jun 20, 2026

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
A versatile preparation of Geländer-type p-terphenyls from a readily available diacetylenic precursor
Matthew Modjewski1, Sergey V Lindeman, Rajendra Rathore
1Department of Chemistry, Marquette University, P.O. Box 1881, Milwaukee, Wisconsin 53201, USA.
Abstract:
A series of doubly bridged p-terphenyls (4) have been synthesized utilizing a facile three-step synthesis starting from the readily available diacetylenic precursor (1) in excellent overall yields, and their structures were confirmed by 1H/13C NMR spectroscopy as well as by X-ray crystallography. The racemization barrier between the meso and chiral atropisomers of one of the derivatives of 4 was found to be approximately 12 kcal/mol by variable-temperature NMR spectroscopy. The versatility of the protocol developed herein was further demonstrated by the preparation of a quadruply bridged penta-p-phenylene derivative.
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