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Formation of macrocyclic ring systems by carbonylation of trifunctional P/B/B frustrated Lewis pairs.

ABSTRACT: The trifunctional P/B/B frustrated Lewis pairs 11a-c featuring bulky aryl groups at phosphorus [Dmesp (a), Tipp (b), Mes* (c)] react with H2 by heterolytic hydrogen splitting followed by cleavage of HB(C6F5)2 to give the zwitterionic six-membered heterocyclic PH phosphonium/borate products 14a-c. Compounds 11a,b react with carbon monoxide by means of a Lewis acid induced CO insertion/rearrangement sequence that eventually results in the formation of the macrocyclic dimers 17a,b. The respective carbonylation reaction of the Mes*P/B/B FLP gives the macrocyclic trimer 18c. The new products were characterized spectroscopically and by X-ray diffraction and the reaction mechanism was analyzed by DFT calculations.

SUBMITTER: Wang L

PROVIDER: S-EPMC5890323 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Formation of macrocyclic ring systems by carbonylation of trifunctional P/B/B frustrated Lewis pairs.

Wang Long L Dong Shunxi S Daniliuc Constantin G CG Liu Lei L Grimme Stefan S Knitsch Robert R Eckert Hellmut H Hansen Michael Ryan MR Kehr Gerald G Erker Gerhard G

Chemical science 20171214 6

The trifunctional P/B/B frustrated Lewis pairs 11a-c featuring bulky aryl groups at phosphorus [Dmesp (a), Tipp (b), Mes* (c)] react with H2 by heterolytic hydrogen splitting followed by cleavage of HB(C6F5)2 to give the zwitterionic six-membered heterocyclic PH phosphonium/borate products 14a-c. Compounds 11a,b react with carbon monoxide by means of a Lewis acid induced CO insertion/rearrangement sequence that ...[more]

PMID: 29675199

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