Bicyclo partial hydrogenation

Subsequently partial hydrogenation of trans,trans- and of cw,c/ -2,8-decadiene-4,6-diyne over a Lindlar catalyst resulted in trans- and cw-7,8-dimethyl bicyclo[4.2.0]octa-2,4-diene, respectively (Scheme 9.48). " ... 

The hydrogenation of 109 over palladium on charcoal in acidic methanol produced (l/ ,7aA)-l,3-diphenyl-5,6,7,7a-tetrahydro-1 //-pyrrolo[ 1,2-r]imidazolc 110 in 61% isolated yield (Equation 14). This reaction was totally unexpected and the authors proposed a mechanism that explains this transformation <2005JOC2368>. The mechanism is shown in Scheme 13. Many of the steps are interchangeable, but the end product is the same. The partial racemization observed could occur by epimerization of the phenyl-substituted carbon adjacent to the imine produced after the cleavage of the bicyclo-adduct. 

A large number of dibasic acids and anhydrides are used in the preparation of poly(ester amide)s. These include terephthalic acid, phthalic anhydride, isophthalic acid, endic endo-cis bicyclo(2,2,10-5)-heptene-2,3-dicarboxylic] anhydride, hydrogenated endic anhydride, maleic anhydride, fumaric acid, dichloromaleic anhydride, itaconic acid, brassylic acid, dimer acid, adipic acid, sebacic acid, succinic acid, trimeUitic anhydride, pyrromellitic anhydride and ethylenediamine tetraacetic acid (EDTA). However, tri- and poly-functional compounds are used only partially and are combined with bifunctional derivatives, or derivatives of previously prepared multifunctional compounds which are subsequently polymerised with bifunctional compounds. 

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