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Synthesis and Stereochemical Characterization of a Novel Chiral α-Tetrazole Binaphthylazepine Organocatalyst.

ABSTRACT: A novel α-tetrazole-substituted 1,1'-binaphthylazepine chiral catalyst has been synthesized and its absolute configuration has been determined by DFT computational analysis of the vibrational circular dichroism (VCD) spectrum of its precursor. The VCD analysis, carried out through the model averaging method, allowed to assign the absolute configuration of a benzylic stereocenter in the presence of a chiral binaphthyl moiety. The 1,1'-binaphthylazepine tetrazole and the nitrile its immediate synthetic precursor, have been preliminarily tested as chiral organocatalysts in the asymmetric intramolecular oxa-Michael cyclization of 2-hydroxy chalcones for the synthesis of chiral flavanones obtaining low enantioselectivity.

SUBMITTER: Summa A

PROVIDER: S-EPMC9413694 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Synthesis and Stereochemical Characterization of a Novel Chiral α-Tetrazole Binaphthylazepine Organocatalyst.

Summa Assunta A Scafato Patrizia P Belviso Sandra S Monaco Guglielmo G Zanasi Riccardo R Longhi Giovanna G Abbate Sergio S Superchi Stefano S

Molecules (Basel, Switzerland) 20220811 16

A novel α-tetrazole-substituted 1,1'-binaphthylazepine chiral catalyst has been synthesized and its absolute configuration has been determined by DFT computational analysis of the vibrational circular dichroism (VCD) spectrum of its precursor. The VCD analysis, carried out through the model averaging method, allowed to assign the absolute configuration of a benzylic stereocenter in the presence of a chiral binaphthyl moiety. The 1,1'-binaphthylazepine tetrazole and the nitrile its immediate synt ...[more]

PMID: 36014353

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