Lloyd D. Taylor

Environmentally benign synthesis using crystal engineering : Steric accommodation in non-covalent derivatives of hydroquinones

The solid state phase behavior of hydroquinone 1 with bis-(N,N-diethylamino)terephthalamide 2 and with bis-(N,N-dimethylamino)terephthalamide 3 has been investigated. Stoichiometric cocrystals have been prepared of the identified stable complexes. X-ray structure determinations of these cocrystals have been performed. The role of the alkyl side chains in the crystal packing geometry is discussed.

Synthesis and reactivity of highly versatile VDMO-VBC copolymers

SummaryThe synthesis of a copolymer containing two reactive functional groups is described. The reactive monomers are 2-vinyl-4,4-dimethyl-5-oxazolone (VDMO), I and vinylbenzyl chloride (VBC), III The resulting polymer is then reactive in two different ways and can produce many different kinds of polymers with specific properties.

Kinetics and mechanism of the alkaline release of phenyl(mercapto)tetrazoles from α-oximes

Compounds such as α-phenyl(mercapto)tetrazole (PMT) oxime (9) undergo rapid elimination of the PMT anion in base via a nitrosoene intermediate. Solution kinetics and HPLC analysis of reaction products are consistent with the mechanism shown in Scheme 2. For open chain oximes such as 4, substitution α to the oxime increases the rate of release of PMT and is attributed to the relief of strain when a crowded reactant is converted to a less-crowded product. For cyclic oximes, the six-membered ring compounds are more reactive than the corresponding five-membered compounds. A linear isokinetic relationship between the entropy and enthalpy of activation was found with β= 346 ± 51 K. Entropies of activation were found to range from –7 to +24 c.u. (1 c.u. = 4.184 J mol–1 K–1) and support the proposed mechanism.