3-Pyridylacrylic acid

Dimerizations of alkenes bearing heteroaromatic substituents such as pyridine have been widely reported. 2-(/ -Styryl)quinoline (239), for example, yields on irradiation in the solid state a dimer which can be represented either as the head-to-head dimer (240) or the head-to-tail dimer (241).225 The stereochemistry of ring fusion in this and many other related dimers is not known. The structures of the dimers obtained by solid state photolysis of /3-2-furyl-, jg-2-thienyl-, and /9-3-pyridylacrylic acid have been interpreted in terms of crystal packing.226... 

If substrates contain nitrogen bases capable of complexing to the metal, this usually has an adverse effect on the hydrogenation reaction. Dobler and coworkers found that enantioselective hydrogenation of (X) -2 -acy lamino-3- and 4-pyridylacrylic acids using Rh/Propraphos did not proceed at room temperature and 1 bar H2 pressure [38]. Drawing the obvious conclusion that this may be a... 

The corresponding /3-4-pyridylacrylic acid was reduced in aqueous ammoniacal solution with Raney nickel at 190° and 40 atm (59). The product of reduction was not identified per se but was converted to the ethyl ester. 

Cinnamic acid, 4-pyridylacrylic acid and their related compounds in solid and crystalline states were photochemically dimerized to give [2 + 2]... 

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