Direct cross-coupling between alkenes and tetrahydrofuran with a platinum-loaded titanium oxide photocatalyst. Issue 10 (12th April 2018)

• Record Type: Journal Article
• Authors: Tyagi, Akanksha; Yamamoto, Akira; Yamamoto, Muneaki; Yoshida, Tomoko; Yoshida, Hisao
• Is Part Of: Catalysis science & technology. Volume 8:Issue 10(2018)
• Page Start: 2546
• Page End: 2556
• Publication Date: 2018-04-12
• Subjects: Catalysis -- Periodicals; 541.395
• DOI: 10.1039/c8cy00129d
• Languages: English
• ISSNs: 2044-4753

Abstract

Abstract : A Pt-loaded TiO2 photocatalyst successfully catalyzed the direct cross-coupling between various alkenes and tetrahydrofuran (THF) without any additional oxidizing agent. Abstract : A Pt-loaded TiO2 photocatalyst successfully catalyzed the direct cross-coupling between various alkenes and tetrahydrofuran (THF) without any additional oxidizing agent. The reaction between cyclohexene and THF gave three cross-coupling products, namely, 2-cyclohexyltetrahydrofuran (A ), 2-(cyclohex-2-en-1-yl)tetrahydrofuran (B ) and 2-(cyclohex-1-en-1-yl)tetrahydrofuran (C ), along with gaseous hydrogen. The mechanistic study revealed that these products were formed through different individual mechanisms: successive addition of two radical species, a 2-tetrahydrofuranyl radical and a hydrogen radical, to the double bond of cyclohexene forA, coupling of a 3-cyclohexenyl radical and a 2-tetrahydrofuranyl radical forB, and 2-tetrahydrofuranyl radical addition and hydrogen radical elimination at the double bond of cyclohexene forC . Among these three mechanisms, those forB andC are dehydrogenative. In this photocatalytic reaction system, since the cyclohexene molecule has enough reactivity, due to the localized π electron density, the Pt nanoparticles loaded on the TiO2 function not as a metal catalyst but as an electron receiver to enhance the charge separation, although the dehydrogenative cross-coupling of benzene with THF requires Pd metal catalysis.