The ring-expansion reactions of cyclobutenediones and related molecules by transition metal complexes.

The thesis is divided into four chapters: (1) Introduction (2) Results and discussion on the reactions of cyclobutenedione derivatives and related molecules with low-valent transition metal complexes. (3) A kinetic study of the ring-expansion reactions of some cyclobutenedione derivatives by platinum(O) complexes and (4) Experimental. Chapter 1. This chapter gives a general survey of the reactions of organic molecules containing small rings with transition metal complexes. The review concentrates on three-and four-membered ring compounds having both electron-donating and electron-withdrawing substituents in their reactions with the later transition metals. Particular accent is placed on the metals iron, rhodium, palladium and platinum. Chapter 2. The reactions of cyclobutenedione derivatives and related molecules with transition metal complexes are discussed. Hypotheses are put forward to account for the variation of products found in these reactions when both the nature of the substituent groups in the organic molecule and the transition metal complex are changed.The spectroscopy results obtained for these complexes are discussed. Chapter 3. A kinetic study of the ring-expansion reactions of some cyclobutenedione derivatives by platinum(O) complexes is described. The reactivities of the species Pt(PPh3)2 and Pt(AsPh3)2 are compared, and a theory concerning the solution characteristics of Pt(AsPh3)2 is put forward. Chapter 4. All experimental details are given for the reactions studied in chapters 2 and 3. All analysis results, infrared and n.m.r. spectra are detailed.