Preparation via Sterically Promoted SN2′ Substitution and Structural Characteristics of a Mes*‐Substituted Tertiary Ethynylphosphine. Issue 5 (27th May 2014)

• Record Type: Journal Article
• Authors: Ito, Shigekazu; Nanko, Masaki; Mikami, Koichi
• Is Part Of: Heteroatom chemistry. Volume 25:Issue 5(2014:Sep.)
• Page Start: 422
• Page End: 427
• Publication Date: 2014-05-27
• Subjects: Heterocyclic chemistry -- Periodicals; 547.59
• DOI: 10.1002/hc.21182
• Languages: English
• ISSNs: 1042-7163

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>The reaction of a sterically encumbered 2‐bromo‐3‐silyloxyphosphapropene [(<italic>Z</italic>)‐Mes*‐P = C(Br)CH(OSiMe₃)Mes; Mes* = 2, 4, 6‐<italic>t</italic>Bu₃C₆H₂, Mes = 2, 4, 6‐Me₃C₆H₂] and butyllithium afforded a bulky ethynylphosphine [Mes*P(<italic>n</italic>Bu)C≡CMes] via S_N2′ reaction of the alkyllithium and subsequent beta‐elimination of HBr. The orbital‐controlled reaction and prohibition of the halogen–metal exchange would be induced by the steric encumbrance of the mesityl group. Structural characteristics of the novel ethynylphosphine were also discussed in views of steric encumbrance as well as stereochemistry. The remarkable distortion of Mes* aromatic ring was further discussed according to DFT calculations.</p> </abstract>