Polyphenylene-based solid acid as an efficient catalyst for activation and hydration of alkynes

DOI: 10.1021/acs.chemmater.0c01763

Authors: Yiyun Liu (University College London) , Bolun Wang (University College London) , Liqun Kang (University College London) , Apostolos Stamatopoulos (University College London) , Hao Gu (University College London) , Feng Ryan Wang (University College London)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Chemistry Of Materials

State: Published (Approved)
Published: May 2020
Diamond Proposal Number(s): 22572 , 21641

Abstract: Porous polymer catalysts possess the potential to combine the advantages of heterogeneous and homogeneous cataly-sis, namely easy post-reaction recycling and high dispersion of active sites. Here we designed a -SO3H functionalized polyphenylene (PPhen) framework with purely sp2-hybridized carbons, which exhibited high activity in the hydration of alkynes including challenging aliphatic substrates such as 1-octyne. The superiority of the structure lies in its cova-lent crosslink in the xy-plane with π-π stacking interaction between the planes, enabling simultaneously high swella-bility and porosity (653 m2·g-1). High acidic sites density (2.12 mmol/g) was achieved at mild sulfonation condition. Similar turnover frequencies (0.015 ± 0.001 min-1) were obtained regardless of acidic density and crosslink content, suggesting high accessibility for all active sites over PPhen. In addition, the substituted benzene groups can activate alkynes through a T-shape CH/π interaction, as indicated by the 8 cm-1 and 16 cm-1 red shift of the alkyne C-H stretch-ing peak for phenylacetylene and 1-octyne repectively in the IR spectra. These advantages render PPhen-SO3H a prom-ising candidate as a solid catalyst replacing the highly toxic liquid phase acids such as the mercury salt.

Subject Areas: Chemistry, Materials

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