Aromatic Ketones with Pentacarbonylmethylmanganese I

Preparation of the starting materials Mn(CO)s(CH3) and the phosphine-substituted derivative [cis-Mn(CO)4(PPh3)(CH3)] follow those from the literature. Solvents are dried over 4A molecular sieves and purged with nitrogen before use (except for chromatography). Silica gel for chromatography was obtained from Baker. All reactions should be carried out under an inert atmosphere but after cooling may be worked up in air (however, solutions of the products slowly decompose in air). 

A SOO-mL three-neck round-bottomed flask equipped with an overhead mechanical stirrer and nitrogen bubbler is flushed with nitrogen and charged 

The desired metallation product 5 is prepared in four steps. Chromatographi-cally separated products are sufficiently pure for successive steps without recrystallization. 

A 200-mL round-bottomed flask equipped with a reflux condenser, nitrogen bubbler, and magnetic stirring bar is flushed with nitrogen and charged with Mn(CO)sCH3 (2.1 g, 10 mmol), triphenylphosphine (2.6 g, 

The first pale yellow band elutes as a virtually colorless solution, which upon removal of solvent and recrystallization from diethyl ether-hexane, yields snow white crystals (0.5 g, 1.2 mmol) of the metallation product, I. 

OCTACARBONYL-1 k4C, 2k4C-ji-[CARBONYL-1 kC 2kO-[(3-DIPHENYLPHOSPHINO-1 kP)-o-PHENYLENE 2kC2] ]-DIMANGANESE, 5 

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