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The Nebraska nonpartisan legislature serves as a control setting for testing several hypotheses about the impact of party and constituency on voting behavior in legislative bodies. Specifically, in light of the data obtained from a setting where party identification is present but party leadership and organization are absent, the following hypotheses are examined: that political parties are important in structuring voting behavior because of the influence of party leaders and organization; that party is important because party identification is a surrogate for sets of beliefs and attitudes that distinguish members of one party from another; or that party is important because party differences reflect different constituency bases of the party. In a roll-call analysis of five sessions utilizing Guttman-scaling and regression techniques, it was found that in the absence of party leadership and organization, voting is highly unstructured. Further, dimensions of voting that were found are largely unexplainable in terms of standard party and constituency variables. Thus, party identification and constituency influence appear to be insufficient cues for the organization of legislative voting behavior, in the absence of party leadership.

Chemical-shift nonequivalence in the room-temperature spectrum of (V-(l,2,3-trimethyl-2-butenylidene)benzenesulfonamide (1) indicates the presence of two isomers in solution resulting from syn-anti isomerism. Using nuclear magnetic resonance spectroscopy the ratio of the isomers in solution at room temperature was determined to be 1.7, with the low-field isomer predominating. However, crystallization of 1 yields the minor upfield isomer exclusively. Equilibrium studies indicate that entropy, rather than enthalpy, is the predominant factor determining the stabilities of the two isomers at temperatures above 150°K. The activation parameters for stereomutation of 1 have been determined using complete line-shape analysis (CLS) and by a combination of rates determined by CLS with rates determined by equilibration at low temperatures. The comparison of Arrhenius data obtained using both procedures indicates that the exclusive use of CLS may prove to be unreliable but that when used in conjunction with another method, accurate results can be obtained. In addition, the free energy of activation at the coalescence temperature obtained from CLS was compared with that calculated using the approximate equation k = irSvjy/l. The two were found to be essentially the same. The mechanisms that have been proposed for synanti isomerism in imines, nitrogen inversion, torsion about the carbon-nitrogen double bond, and a mechanism intermediate between these two extremes, have been critically discussed. The JV-benzenesulfonyl group has been found to be more effective at lowering the barrier to syn-anti isomerism than an JV-phenyl substituent. This result indicates that the mechanism of isomerization cannot be pure inversion, but that the mechanism has some torsional character.he stereochemical properties of the carbon-nitrogen double bond have been the subject of numerous investigations in recent years.3-10 Of particular concern has been the question of the mechanism of stereomutation in these compounds. In some respects, this controversy has paralleled that concerning the mechanism of conformational interchange in acyclic trisubstituted nitrogen compounds which bear heteroatoms bonded to nitrogen. The identity of the slow conformational change in such compounds including amino-

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