Acid‐Catalyzed Regioselective Synthesis of α‐Diarylmethyl Substituted Phenols and para‐Quinone Methides in Water. Issue 8 (22nd July 2022)

• Record Type: Journal Article
• Authors: Xiong, Biquan; Shang, Wenli; Xu, Weifeng; Liu, Yu; Tang, Ke‐Wen; Wong, Wai‐Yeung
• Is Part Of: Asian journal of organic chemistry. Volume 11:Issue 8(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-22
• Subjects: Brønsted-acid catalysis -- Green media -- Hydroarylation -- para-Quinone methides -- Phenols; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; 547.005
• DOI: 10.1002/ajoc.202200295
• Languages: English
• ISSNs: 2193-5807

Abstract

Abstract: A facile and efficient method for the synthesis of α ‐diarylmethyl substituted phenols from para ‐quinone methides ( p ‐QMs) with phenols has been developed by using phosphoric acid as the catalyst and water as the green solvent under mild conditions. In addition, when TEMPO was added as an additive for the reaction, the diaryl‐substituted para ‐quinone methides could be generated as the target product. The reactions show high functional group tolerance, good to excellent yields and unique selectivity, and a broad range of α ‐diarylmethyl motif containing phenol(s) and quinones could be prepared through the divergent methods. Furthermore, a series of control experiments were performed to gain the insights of the plausible mechanisms. These protocols have a high atomic economy, and may have significant implications for the construction of C( sp 3 )−C( sp 2 ) bonds in organic synthesis. Abstract : Divergent green synthesis : A facile and efficient method for the synthesis of α ‐diarylmethyl substituted phenols from para ‐quinone methides ( p ‐QMs) with phenols has been developed by using phosphoric acid as the catalyst and water as the green solvent under mild conditions. In the presence of TEMPO, the diaryl‐substituted para ‐quinone methids could be generated as the major product selectively. These protocols are cheap, easy to scale‐up, avoid the use of expensive/hazardous transition metal salts and special ligands, and also may have significant implications for the construction of C( sp 3 )−C( sp 2 ) bonds in organic synthesis.