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Dissipative Catalysis with a Molecular Machine.

ABSTRACT: We report on catalysis by a fuel-induced transient state of a synthetic molecular machine. A [2]rotaxane molecular shuttle containing secondary ammonium/amine and thiourea stations is converted between catalytically inactive and active states by pulses of a chemical fuel (trichloroacetic acid), which is itself decomposed by the machine and/or the presence of additional base. The ON-state of the rotaxane catalyzes the reduction of a nitrostyrene by transfer hydrogenation. By varying the amount of fuel added, the lifetime of the rotaxane ON-state can be regulated and temporal control of catalysis achieved. The system can be pulsed with chemical fuel several times in succession, with each pulse activating catalysis for a time period determined by the amount of fuel added. Dissipative catalysis by synthetic molecular machines has implications for the future design of networks that feature communication and signaling between the components.

SUBMITTER: Biagini C

PROVIDER: S-EPMC6900173 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Dissipative Catalysis with a Molecular Machine.

Biagini Chiara C Fielden Stephen D P SDP Leigh David A DA Schaufelberger Fredrik F Di Stefano Stefano S Thomas Dean D

Angewandte Chemie (International ed. in English) 20190621 29

We report on catalysis by a fuel-induced transient state of a synthetic molecular machine. A [2]rotaxane molecular shuttle containing secondary ammonium/amine and thiourea stations is converted between catalytically inactive and active states by pulses of a chemical fuel (trichloroacetic acid), which is itself decomposed by the machine and/or the presence of additional base. The ON-state of the rotaxane catalyzes the reduction of a nitrostyrene by transfer hydrogenation. By varying the amount of ...[more]

PMID: 31111628

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