Work

Gold-Catalyzed Cyclizations of 4-Alkyl-2-yn-1-yl (Oxy)cyclohexa-2,5-dien-1-ones ( 1 ) to Develop Two Cyclizations via π-Alkyne versus π-Allene Activations

Year: 2026

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide This work reports two new gold-catalyzed cyclizations of 4-alkyl-2-yn-1-yl (oxy)cyclohexa-2,5-dien-1-ones ( 1 ) via gold−π-allene versus gold−π-alkyne routes, The π-allene route involves a [3.3] Claisen rearrangement of 1-alloxyallene intermediates to enable a 1,3-group migration, ultimately affording 2-substituted 3-formylbenzofurans ( 2 ). Density functional theory (DFT) calculations support this proposed mechanism in which water plays a key role. An alternative π-alkyne route contains cocatalyst PhNH 2 (10 mol %), leading to the formation of C 3,4 -fused tetrahydrobenzofuran-5(4 H )-ones ( 3 ) stereoselectively.

Source: Organic Letters

DOI: 10.1021/acs.orglett.5c05132

Authors: Akshay Suresh Kshirsagar, Pei-Qin Liao, Tzuhsiung Yang, Rai-Shung Liu

Institution: National Tsing Hua University

Language: English

Topic: Catalytic Alkyne Reactions

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,500

Funder: National Science and Technology Council