Publications by authors named "Martin T Mwangi"

The hydrogen-bond-acceptor (HBA) templates 2,3-bis(4-methylenethiopyridyl)naphthalene (2,3-nap) and 1,8-bis(4-pyridyl)naphthalene (1,8-dpn) are used to assemble (E,E)-2,5-dimethylmuconic acid (dmma) in the solid state for an intermolecular [2 + 2] photocycloaddition. Co-crystallisation of 2,3-nap with dmma affords an 1D hydrogen-bonded polymer that is photostable while 1,8-nap affords a 0D hydrogen-bonded assembly that is photoactive. The diene stacks in-phase and reacts to give a syn monocyclobutane in up to 55% yield.

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Incompatible Grubbs catalyst and an osmium dihydroxylation catalyst were site-isolated from each other using polydimethylsiloxane thimbles. The Grubbs catalyst was added to the interior of the thimbles, and AD-mix-alpha/beta was added to the exterior. Organic substrates readily fluxed through the walls of the thimbles and reacted with each catalyst.

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The development of a method for site-isolation of Grubbs second-generation catalyst from MCPBA is described. In these reactions, Grubbs catalyst was dissolved in a solvent consisting of a mixture (1:1 v/v) of 1-butyl-3-methylimidazolium hexafluorophosphate and methylene chloride and completely encapsulated within a thimble fabricated from polydimethylsiloxane (PDMS). A series of molecules that react by cross metathesis or ring-closing metathesis were added to the interior of the thimble and allowed to react.

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Delta-octalactone, produced by several Bovidae, has been suggested as a potential repellant of tsetse fly attack. Racemic delta-octalactone was synthesized via an abbreviated route. The product was assayed against 3-day old starved teneral female tsetse flies, Glossina morsitans morsitans Wiedemann (Diptera: Glossinidae), in a choice wind tunnel and found to be a potent tsetse repellent at doses >or=0.

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The Grubbs' first and second generation catalysts were occluded into cross-linked slabs of polydimethylsiloxane with volumes from 1 mm3 to 1 cm3 by swelling the polymer with catalyst and methylene chloride. Methylene chloride was evaporated under vacuum to yield occluded catalysts where their solvent was polydimethylsiloxane. These occluded catalysts were reacted with alkenes dissolved in H2O or H2O/MeOH mixtures that diffused into the polydimethylsiloxane to react by ring-closing metathesis and cross metathesis.

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