Small ring compounds metal-catalyzed

Reductive and oxidative transformations of small ring compounds form the basis of a variety of versatile synthetic methods which include functionalization and carbon skeleton construction. Redox mechanisms of organotransition metal compounds play an important role in inducing or catalyzing specific reactions. Another useful route in this area is based on one-electron redox reactions. The redox tautomerism of dialkyl phosphonate also contributes to the efficiency of the reductive transformation of small ring compounds. This review summarizes selective transformations which have a high potential for chemical synthesis. 

Redox reactions are considered as being able to provide versatile and efficient methods for bringing about ring transformations. Transition metal complexes in particular are able to induce or catalyze oxidative or reductive transformations of small ring compounds. Organometallics, such as metal-lacycles derived by the insertion of metal atoms into rings, are involved as key intermediates in many cases, allowing subsequent functionalization or carbon-carbon bond formation. 

Metal-catalyzed Cycloaddition of Small Ring Compounds... 

In light of all this, it is not surprising that Bishop in his review on transition metal promoted rearrangement of small-ring compounds concludes No class of transition metal catalyzed rearrangements has been the subject of more controversy than those of bicyclobutane. ... 

Ohta T, Takaya H (1991) Metal-catalyzed cycloaddition of small ring compounds. In Trost BM, Fleming I (eds) Comprehensive organic synthesis, vol 5. Pergamon, Oxford, p 1185... 

Metal-Catalyzed Cycloaddition of Small Ring Compounds. T. Ohta and H. Takaya, Comp. Org. Synth., 1991, 5, 1185-1205. 

Abstract Development in the field of transition metal-catalyzed carbonylation of epoxides is reviewed. The reaction is an efficient method to synthesize a wide range of / -hydroxy carbonyl compounds such as small synthetic synthons and polymeric materials. The reaction modes featured in this chapter are ring-expansion carbonylation, alternating copolymerization, formylation, alkoxycarbonylation, and aminocarbonylation. 

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