One‐Pot Alkynylation of Azaaryl Aldehydes and Spontaneous Base‐Free Rearrangement into Enone Esters: an Autoinductive Mechanism. Issue 12 (30th March 2018)

• Record Type: Journal Article
• Authors: Sieng, Bora; Maldonado, Matias Funes; Romagnoli, Carlo; Amedjkouh, Mohamed
• Is Part Of: European journal of organic chemistry. Issue 12(2018)
• Page Start: 1491
• Page End: 1495
• Publication Date: 2018-03-30
• Subjects: Alkyne addition -- Isomerisation -- Enone esters -- Rearrangement -- Synthetic methods; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201701566
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract : A direct synthesis of γ‐oxo‐α, β‐unsaturated esters has been developed. When heteroaromatic aldehydes are reacted with deprotonated ethyl propiolate, in the presence of Me2 Zn or BuLi, the newly formed propargylic alcohol rearranged spontaneously to give the corresponding unsaturated keto ester. Isotope labeling, allenol intermediate trapping and crossover experiments provided insight into the reactive sequence and suggest an autocatalytic mechanism. Abstract : Spontaneous rearrangement of heteroaromatic alkynols into enones involves an autocatalytic mechanism.