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Updated: Jan 18, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Ligand-Controlled Stereodivergent Hydroalkynylation of Purine Allenamines to Access Functionalized trans- and
Stephin Baby1, Akash P Sakla1, Bichismita Sahu1
1Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gujarat 382355, India.
Abstract:
Herein, we report an easily tunable and regioselective Pd-catalyzed allene-alkyne coupling protocol for the stereodivergent synthesis of E- and Z-1,3-enynes using purine allenamine by a simple switch of ligands P(p-tolyl)Ph2 and Boc-Phe-OH. For the first time, we have explored mono-N-protected amino acids (MPAAs) as ligands in allene-alkyne coupling to furnish Z-1,3-enynes selectively. This protocol streamlined the access to chiral 1,3-enynes and addressed the long-standing stereoselectivity challenges associated with 1,3-enynes from allene-alkyne coupling.
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