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Exploring the Reactivity of a Frustrated Sn/P Lewis Pair: The Highly Selective Complexation of the cis-Azobenzene Photoisomer.

ABSTRACT: The reactivity of the geminal frustrated Lewis pair (FLP) (F₅ C₂ )₃ SnCH₂ P(tBu)₂ (1) was explored by reacting it with a variety of small molecules (PhOCN, PhNCS, PhCCH, tBuCCH, H₃ CC(O)CH=CH₂ , Ph[C(O)]₂ Ph, PhN=NPh and Me₃ SiCHN₂ ), featuring polar or non-polar multiple bonds and/or represent α,β-unsaturated systems. While most adducts are formed readily, the binding of azobenzene requires UV-induced photoisomerization, which results in the highly selective complexation of cis-azobenzene. In the case of benzil, the reaction does not lead to the expected 1,2- or 1,4-addition products, but to the non-stereoselective (tBu)₂ PCH₂ -transfer to a prochiral keto function of benzil. All adducts of 1 were characterised by means of multinuclear NMR spectroscopy, elemental analyses and X-ray diffraction experiments.

SUBMITTER: Holtkamp P

PROVIDER: S-EPMC7986075 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Exploring the Reactivity of a Frustrated Sn/P Lewis Pair: The Highly Selective Complexation of the cis-Azobenzene Photoisomer.

Holtkamp Philipp P Poier Dario D Neumann Beate B Stammler Hans-Georg HG Mitzel Norbert W NW

Chemistry (Weinheim an der Bergstrasse, Germany) 20210128 11

The reactivity of the geminal frustrated Lewis pair (FLP) (F5 C2 )3 SnCH2 P(tBu)2 (1) was explored by reacting it with a variety of small molecules (PhOCN, PhNCS, PhCCH, tBuCCH, H3 CC(O)CH=CH2 , Ph[C(O)]2 Ph, PhN=NPh and Me3 SiCHN2 ), featuring polar or non-polar multiple bonds and/or represent α,β-unsaturated systems. While most adducts are formed readily, the binding of azobenzene requ ...[more]

PMID: 33284497

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