Decarboxylation, of dicarboxylic acids

Regioselectivity of C—C double bond formation can also be achieved in the reductiv or oxidative elimination of two functional groups from adjacent carbon atoms. Well estab llshed methods in synthesis include the reductive cleavage of cyclic thionocarbonates derivec from glycols (E.J. Corey, 1968 C W. Hartmann, 1972), the reduction of epoxides with Zn/Nal or of dihalides with metals, organometallic compounds, or Nal/acetone (seep.lS6f), and the oxidative decarboxylation of 1,2-dicarboxylic acids (C.A. Grob, 1958 S. Masamune, 1966 R.A. Sheldon, 1972) or their r-butyl peresters (E.N. Cain, 1969). 

Double decarboxylation of 1,2-dicarboxylic acids may take place smoothly in an aqueous 90% pyridine-Et3N-(Pt) electrolysis system to give olefins in fair yields [158-160]. Some representative examples are shown in Eqs. (39) [14], (40) [13,15,16], and (41) [160] ... 

In a joint publication three groups report that oxidative decarboxylation of 1,2-dicarboxylic acids generally proceeds in higher yields upon electrolysis than with lead tetraacetate [P. C. Radlick et al., J. J. Sims, and E. E. van Tamelen and T. Whitesides, Tetrahedron Letters, 5117 (1968)]. A similar conclusion was reported independently and simultaneously by H. H. Westberg and H. J. Dauben, Jr. [ibid., 5123(1968)]. 

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See also in sourсe #XX -- [ , , , ]

See also in sourсe #XX -- [ , , , ]

See also in sourсe #XX -- [ , , , ]

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