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Asymmetric Synthesis of Second-Generation Light-Driven Molecular Motors.

ABSTRACT: The enantiomeric homogeneity of light-driven molecular motors based on overcrowded alkenes is crucial in their application as either unidirectional rotors or as chiral multistate switches. It was challenging to obtain these compounds as single enantiomers via the established synthetic procedures due to loss of optical purity in the key step, i.e., the Barton-Kellogg olefination reaction. Searching for strategies to avoid racemization, a new class of light-driven molecular motors was designed, synthesized, and studied. The stereochemical integrity was fully preserved throughout the synthesis, and on the basis of photochemical and kinetic studies using UV/vis, CD, and ¹H NMR spectroscopy, it was established that they still function properly as unidirectional molecular motors.

SUBMITTER: van Leeuwen T

PROVIDER: S-EPMC5442604 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Asymmetric Synthesis of Second-Generation Light-Driven Molecular Motors.

van Leeuwen Thomas T Danowski Wojciech W Otten Edwin E Wezenberg Sander J SJ Feringa Ben L BL

The Journal of organic chemistry 20170501 10

The enantiomeric homogeneity of light-driven molecular motors based on overcrowded alkenes is crucial in their application as either unidirectional rotors or as chiral multistate switches. It was challenging to obtain these compounds as single enantiomers via the established synthetic procedures due to loss of optical purity in the key step, i.e., the Barton-Kellogg olefination reaction. Searching for strategies to avoid racemization, a new class of light-driven molecular motors was designed, sy ...[more]

PMID: 28459576

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