Guanidinium Chlorochromate, a New, Efficient, and Mild Oxidizing Agent for Benzylic and Other Alcohols to Carbonyl Compounds in Water and Organic Solvents

Abstract

Guanidinium chlorochromate (GCC) has been first reported as a new oxidizing agent for the oxidation of a series of benzylic and a number of other aliphatic and aromatic alcohols to carbonyl compounds and quinones respectively in water in the presence of a phase-transfer catalyst and also in an organic solvent such as methylenechloride.

Two New 1,1,3,3-Tetramethylguanidinium Halochromates (C5H14N3CrO3X) (X: Cl, F): Efficient Reagents for Oxidation of Organic Substrates under Solvent-Free Conditions and Microwave Irradiation

“…Since the appearance of Collins reagent [2], significant improvements are achieved in the development of new Cr(VI) based oxidizing agents for the effective and selective oxidation of organic substrates, in particular alcohols, under mild conditions. Some of the important entries in the list of reagents are pyridinium chlorochromate (PCC) [3], pyridinium dichromate (PDC) [4], pyridinium fluorochromate (PFC) [5,6], quinolinium fluorochromate (QFC) [7], 1,1,3,3-tetramethylguanidinium dichromate (TMGDC) [8], quinolinium chlorochromate (QCC) [9], and 3,5-dimethylpyrazolium fluorochromate (DmpzHFC) [10]. However the chromium based reagents that have been developed so far have some limitations that cannot be overlooked.…”

Oxidative transformation of alcohols and organic halides in aqueous solution

“…These derivatives were found to be better in their reactivity and selectivity compared to the traditional Cr oxidants, and offer a benefit of solubility in organic solvents. Recently, guanidinium chlorochromate [GCC] has been used in the presence of a phasetransfer catalyst 24 for the oxidation of different benzylic and aliphatic alcohols in water. Pyridinium chlorochromate [PCC] has been used to oxidize 5,6-dihydropyrans 25 to the corresponding anhydromevalonolactone in dichloromethane in good to excellent yields.…”