Cyclocarbonylative Sonogashira Reactions of 1‐Ethynylbenzyl Alcohols: Synthesis of 1‐Carbonylmethylene‐1, 3‐Dihydroisobenzofurans. Issue 22 (26th June 2015)

• Record Type: Journal Article
• Authors: Aronica, Laura Antonella; Giannotti, Luca; Tuci, Giulia; Zinna, Francesco
• Is Part Of: European journal of organic chemistry. Issue 22(2015)
• Page Start: 4944
• Page End: 4949
• Publication Date: 2015-06-26
• Subjects: Synthetic methods -- Homogeneous catalysis -- Cross‐coupling -- ­Carbonylation -- Cyclisation -- Oxygen ­heterocycles; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201500539
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: In this work, we present a carbonylative Sonogashira reaction of o ‐ethynyl benzyl alcohols and aryl iodides, followed by a cyclization process to selectively give carbonylmethylene isobenzofurans in high yields and in an atom‐economic fashion. The reaction can be carried out in the absence of CuI, with a small amount of PdCl2 (PPh3 )2 (0.2–0.5 mol‐%), using aryl iodides bearing both electron‐withdrawing and electron‐donating groups. Of the two possible stereoisomeric products, Z ‐isobenzofuran derivatives were obtained as major products. But, when the reaction was extended to a secondary alcohol, an interesting switch in stereoselectivity was observed. Abstract : A one‐step synthesis of a set of functionalised dihydroisobenzofurans was accomplished through copper‐free, palladium‐catalysed cyclocarbonylative Sonogashira reactions between ethynylbenzyl alcohols and iodoarenes.