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The introduction of carbonyl functionality using carbonylation in its various forms represents some of the largest volume and most successful applications of homogeneous catalysis in the chemical industry. These reactions have a diversity of mechanisms which, once understood, allow the manipulation of the catalytic processes in unique ways and offers options for interesting reactor designs. This review will focus on the generation of acetates and propionates, two of the simplest entities that can be generated by carbonylation, and discuss how mechanistic knowledge can be used to develop new catalysts and new reactor configurations in carbonylation processes when desired. Examples will include the development of (i) a Rh–MeI–Li catalyzed carbonylation of methyl acetate to acetic anhydride, (ii) a Mo catalyzed carbonylation of ethylene to propionic acid and propionic anhydride, (iii) a molecular Ir–La catalyst supported on carbon for heterogeneous carbonylation of methanol, (iv) alternative reactor designs ...

6-Substituted 2-acetonaphthones can be generated from para substituted benzaldehydes and acetylacetone (2,4-pentanedione) in three reactions consisting of condensing the benzaldehyde with acetylacetone, acetalizing the resultant 3-benzylidene 2,4-pentanedione (α-acetyl benzalacetones), with trimethyl orthoformate, pyrolyzing the acetal either in the vapor phase at 475°C or by heating in a high boiling solvent, such as 1-methylnaphthalene.

The synthesis, characterization, and reactivity of the triphenylmethylphosphonium salts of several anionic ruthenium iodo carbonyl complexes are described. These complexes included the facial and meridional isomers of (Ru(CO)/sub 3/I/sub 3/)/sup -/, and the dimeric dianion (Ru/sub 2/(CO)/sub 4/I/sub 6/)/sup 2 -/. The two (Ru(CO)/sub 3/I/sub 3/)/sup -/ isomers were characterized by their infrared spectra and by the /sup 13/C NMR spectra of /sup 13/CO-enriched samples of these compounds. The dimeric dianion (Ru/sub 2/(CO)/sub 4/I/sub 6/)/sup 2 -/, which was generated by heating the facial isomer under Ar, was characterized by X-ray crystallography and was found to have S/sub 2/ symmetry. (Ph/sub 3/PMe)/sub 2/(Ru/sub 2/(CO)/sub 4/I/sub 6/) crystallizes in the triclinic space group P1-C/sub i//sup 1/ (No. 2) with a = 9.794 (4) A, b = 11.158 (4) A, c = 11.710 (5) A, ..cap alpha.. = 85.01 (3)/sup 0/, ..beta.. = 93.70 (3)/sup 0/, ..gamma.. = 93.70 (3)/sup 0/ and Z = 1. The meridional isomer of (Ru(CO)/sub 3/I/sub 3/)/sup -/ was generated by adding carbon monoxide to the dimeric dianion (Ru/sub 2/(CO)/sub 4/I/sub 6/)/sup 2 -/ at atmospheric pressure. The meridional isomer of (Ru(CO)/sub 3/I/sub 3/)/sup -/ could be used to regenerate the dimeric dianion (Ru/sub 2/(CO)/sub 4/I/sub 6/)/supmore » 2 -/ by heating the complex under Ar in the presence of excess iodide, or it could be used to regenerate the facial isomer by heating the complex under a carbon monoxide atmosphere.« less