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"Nok": a phytosterol-based amphiphile enabling transition-metal-catalyzed couplings in water at room temperature.

ABSTRACT: The third-generation designer amphiphile/surfactant, "Nok" (i.e., SPGS-550-M; ?-sitosterol methoxypolyethyleneglycol succinate), soon to be commercially available from Aldrich, can be prepared in two steps using an abundant plant feedstock and ?-sitosterol, together with succinic anhydride and PEG-550-M. Upon dissolution in water, it forms nanomicelles that serve as nanoreactors, which can be characterized by both cryo-TEM and dynamic light scattering analyses. Several transition-metal-catalyzed reactions have been run under micellar conditions to evaluate this surfactant relative to results obtained in nanoparticles composed of TPGS-750-M (i.e., a second-generation surfactant). It is shown that Nok usually affords yields that are, in general, as good or better than those typically obtained with TPGS-750-M, and yet is far less costly.

SUBMITTER: Klumphu P

PROVIDER: S-EPMC4013797 | biostudies-other | 2014 Feb

REPOSITORIES: biostudies-other

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"Nok": a phytosterol-based amphiphile enabling transition-metal-catalyzed couplings in water at room temperature.

Klumphu Piyatida P Lipshutz Bruce H BH

The Journal of organic chemistry 20140121 3

The third-generation designer amphiphile/surfactant, "Nok" (i.e., SPGS-550-M; β-sitosterol methoxypolyethyleneglycol succinate), soon to be commercially available from Aldrich, can be prepared in two steps using an abundant plant feedstock and β-sitosterol, together with succinic anhydride and PEG-550-M. Upon dissolution in water, it forms nanomicelles that serve as nanoreactors, which can be characterized by both cryo-TEM and dynamic light scattering analyses. Several transition-metal-catalyzed ...[more]

PMID: 24447127

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