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New Insights in Frustrated Lewis Pair Chemistry with Azides.

ABSTRACT: The geminal frustrated Lewis pair (FLP) tBu₂ PCH₂ BPh₂ (1) reacts with phenyl-, mesityl-, and tert-butyl azide affording, respectively, six, five, and four-membered rings as isolable products. DFT calculations revealed that the formation of all products proceeds via the six-membered ring structure, which is thermally stable with an N-phenyl group, but rearranges when sterically more encumbered Mes-N₃ and tBu-N₃ are used. The reaction of 1 with Me₃ Si-N₃ is believed to follow the same course, yet subsequent N₂ elimination occurs to afford a four-membered heterocycle (5), which can be considered as a formal FLP-trimethylsilylnitrene adduct. Compound 5 reacts with hydrochloric acid or tetramethylammonium fluoride and showed frustrated Lewis pair reactivity towards phenylisocyanate.

SUBMITTER: Boom DHA

PROVIDER: S-EPMC6851766 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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New Insights in Frustrated Lewis Pair Chemistry with Azides.

Boom Devin H A DHA Jupp Andrew R AR Nieger Martin M Ehlers Andreas W AW Slootweg J Chris JC

Chemistry (Weinheim an der Bergstrasse, Germany) 20190909 58

The geminal frustrated Lewis pair (FLP) tBu2 PCH2 BPh2 (1) reacts with phenyl-, mesityl-, and tert-butyl azide affording, respectively, six, five, and four-membered rings as isolable products. DFT calculations revealed that the formation of all products proceeds via the six-membered ring structure, which is thermally stable with an N-phenyl group, but rearranges when sterically more encumbered Mes-N3 and tBu-N3 are used. The reaction of 1 wi ...[more]

PMID: 31497899

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