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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Reactions of 2-Diphenylphosphino-benzaldehyde with Group 13 Lewis Acids
Hui Li1,2, Shaoying Ju1, Ting Chen1
1Institute of Drug Discovery Technology and Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, Zhejiang, China.
Abstract:
2-Diphenylphosphinobenzaldehyde 1 reacts with the group 13 Lewis acids to give simple phosphine adducts C6H4P(C(O)H)(Ph)2InX3; X = Br 2 and I 3. In contrast, the Lewis acids GaCl3, AlCl3, E(C6F5)3 (E = B or Al), and ClAl(C6F5)2 affect Lewis acid/phosphine addition to a carbonyl group, affording zwitterions with either the eight-membered ring products [(C6H4C(H)(OER3)P(Ph)2)]2 ER3 = Al(C6F5)3 4, Al(C6F5)2Cl 5, AlCl3 6, or GaCl3 7 or the six-membered ring species (C6H4C(H)(OB(C6F5)3)P(Ph)2(C6H4C(H)(O) P(Ph)2)) 8. These products derived from the frustrated Lewis pair additions to aldehyde fragments are fully characterized and described, and the differing reactivity is considered.
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