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The deuterium decoupled, proton nuclear magnetic resonance spectrum of a sample of diphenylmethane-d 3 dissolved in a nematic liquid crystalline solvent has been analyzed to yield a set of dipolar couplings, D i j . These have been used to test models for the conformational distribution generated by rotation about the two ring-CH 2 bonds through angles 1 and 2 . Conformational distributions, particularly when obtained from a quantum chemistry calculation, are usually described in terms of the potential energy surface, V( 1 , 2 ), which is then used to define a probability density distribution, P( 1 , 2 ). It is shown here that when attempting to obtain P( 1 , 2 ) from experimental data it can be an advantage to do this directly without going through the intermediate step of trying to characterize V( 1, 2 ). When applied to diphenylmethane this method shows that the dipolar couplings are consistent with a conformational distribution centered on 1 ϭ 2 ϭ56.5Ϯ0.5°, which is close to the values calculated for an isolated molecule of 57.0°, and significantly different from the asymmetric structure found in the crystalline state.

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Reliable completely odorless syntheses of soluble copolymeric reagents of styrene type containing propane-1,3-dithiol functions able to convert carbonyl compounds into 1,3-dithiane derivatives and to support other useful transformations are reported together with their progenitor copolymers containing benzenesulfonate or thioacetate groups perfectly stable in open air and suitable for unlimited storage. The effectiveness of the prepared reagents as tools for polymer-supported syntheses to produce ketones by aldehyde umpolung and alkylation is tested in the conversion of benzaldehyde to phenyl n-hexyl ketone starting from copolymers with different contents of active units and molecular weights. To facilitate the adaptation of the prepared soluble copolymeric reagents to other possible applications, a table of solvents and nonsolvents is presented.