Direct Cross‐Couplings of Propargylic Diols. Issue 32 (4th July 2016)

• Record Type: Journal Article
• Authors: Green, Nicholas J.; Willis, Anthony C.; Sherburn, Michael S.
• Is Part Of: Angewandte Chemie international edition. Volume 55:Issue 32(2016)
• Page Start: 9244
• Page End: 9248
• Publication Date: 2016-07-04
• Subjects: alkenes -- allenes -- cross-coupling -- palladium -- synthetic methods; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201604527
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: [Pd(PPh3 )4 ] catalyzes a Suzuki–Miyaura‐like twofold cross‐coupling sequence between underivatized propargylic diols and either aryl or alkenyl boronic acids to furnish highly substituted 1, 3‐dienes. Thus, 2, 3‐diaryl‐1, 3‐butadienes and their dialkenic congeners ([4]dendralenes) are delivered in a (pseudo)halogen‐free, single‐step synthesis which supersedes existing methods. Allenols are also readily formed. Treatment of these single‐ and twofold cross‐coupled products with acid leads to remarkably short syntheses of highly‐substituted benzofulvenes and aryl indenes, respectively. Abstract : Just diene to form from a diol ! Underivatized propargylic diols are now substrates for two‐fold Suzuki–Miyaura couplings and deliver a wide range of highly substituted 1, 3‐dienes in one step. The cross‐coupling reaction is likely facilitated by coordination of boron to the hydroxy groups of the diol, and the product can be used to readily generate a number of highly substituted polyenic systems.