Organo copper metal

An easy synthesis of prenyl naphthoquinones, e.g. menaquinone-2 (205 n = 2), was achieved by coupling the appropriate prenyl halide with an organo-copper derivative of the electrochemically derived quinone bisacetal (216). Menaquinone-2 and phylloquinone (204) were also obtained in good yields by reaction of 2-methyl-1,4-naphthoquinone (205 n =0) with geranyl and phytyl halides in the presence of metal dust. A one-step method for the preparation of vitamin K analogues uses cyclodextrin inclusion catalysts.Thus reaction of the diol (217) with allyl bromide in the presence of oxygen and/3-cyclodextrin at pH 9 afforded the menaquinone analogue (218). 

The decarboxylation of CuOCOC6F5 in quinoline forms CuC6F5, and indeed organo coppers appear generally to be intermediates in the decarboxylation of carboxylic acids, and their catalytic action explains the long-known effectiveness of copper metal or copper salts in such reactions. 

Regarding these topics, special attention was drawn to low-valent alkynyl-stabilized organo-copper(I) and -silver(I) compounds in which the respective metals possess a planar surroimding [14]. While the use of alkyne- and alkynyl-stabilized inorganic and organic group-11 metal fragments have lately been reviewed in detail [14], we focus here on recent results obtained in the field of electron transfer. 

Approximate contents of 14 minor and trace elements in oils produced from three coals by the catalytic hydrogenation process of Gulf Research and Development Co. were determined by emission spectroscopy. The results were compared with corresponding data for the original coals and the solid residues from the process. The contents of ash, sulfur, vanadium, lead, and copper are near or below the limits specified for an oil to be fired directly in a gas turbine while sodium and probably calcium are too high. Titanium appears to be somewhat enriched in the oils analyzed relative to other elements, suggesting its presence in organo-metallic complexes. 

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