Trans-cinnamamide

The total synthesis of casimiroedine (17), isolated from Casimiroa edulis, has been achieved. The synthesis also establishes the trans-cinnamamide stereochemistry, a point which had remained unresolved in the original structural elucidation study. The reaction of the keto-lactone (18) with the imidazolyl-lithium (19) generated in situ yields a number of products,the major ones being the pilocarpine-related (20) and the ditetrahydrofuran (21). Treatment... 

Hosomi, H., Ito, Y, and Ohba, S., Crystal-to-crystal photodimerization of tra s-cinnamamides, Ohba, S., Hosomi, H., and Ito, Y, In situ x-ray observation of pedal-hke conformational change and dimerization of trans-cinnamamide in cocrystals with phthaKc acid, /. Am. Chem. Soc., 123, 6349, 2001. 

These Br nsted-type plots often seem to be scatter diagrams until the points are collated into groups related by specific structural features. Thus, p-nitrophenyl acetate gives four separate, but parallel, lines for reactions with pyridines, anilines, imidazoles, and oxygen nucleophiles.Figure 7-4 shows such a plot for the reaction of trans-cmmm c anhydride with primary and secondary aliphatic amines to give substituted cinnamamides.All of the primary amines without substituents on the a carbon (R-CHi-NHi) fall on a line of slope 0.62 cyclopentylamine also lies on this line. If this line is characteristic of normal behavior, most of the deviations become qualitatively explicable. The line drawn through the secondary amines (slope 1.98) connects amines with the structure R-CHi-NH-CHi-R. The different steric requirements in the acylation reaction and in the model process... 

Four isobutylamide analogs of the natural products were synthesized in order to compare their insecticidal efficacy with that of the natural products. The synthetic scheme for the preparation of cis-fagaramide ( ) is shown in Figure 1. The syntheses of the cis (9) and trans (8) isomers of N -isobutyl-cinnamamide were accomplished by procedures similar to those utilized in the preparation of the cis (7) and trans (1 ) isomers of fagaramide, with the exception that benzaldehyde was used as starting material in the former case, piperonal in the latter. Isobutylbenzamide (10) was synthesized from benzoyl chloride and isobutylamine. 

C9H9NO cinnamamide, predominantly trans 621-79-4 489.83 42.908 2 16499 C9H9N303W triacetonitrile tungsten tricarbonyl 16800-47-8 307.15 25.714 1,2... 

The polymerization conditions typically employ refluxing the precursors in pyridine with catalytic amounts of piperidine for several days (12a), The structure of the trans-cyclohexyl ethyl amino synioregic main chain cinnamamide polymer, 1, (Tg = 208°C) is given in Figure 2. 

Absolute asymmetric synthesis has been performed by controlled reduction in crystal symmetry. The principle is based on selective induction of a guest molecule into a centrosymmetric host structure, thus reducing the symmetry of the mixed crystals. Crystallization of the tra s-cinnamamide host 56 in the presence of the trans-cinnamic acid guest 47 results in the formation of mixed crystals composed of two enantiomorphous halves each containing 0.5 to 1.0% of the acid. Irradiation of each half separately yields the optically active dimers 57a and 57b in excess with an enantiomeric yield in the range of 40 to 60%. This varies from one single crystal to another. 

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