Naphthalene Tricarbonyl Manganese I

The complex was prepared from Mn(CO)5Br16 (1.10g, 4.0 mmol), silver tetrafluoroborate (0.82 g, 4.2 mmol), and naphthalene (0.77 g, 6.0 mmol) by a procedure analogous to that employed for the acenaphthene analogue. The product, a pale yellow solid, was again isolated by filtration, washed with ether, and dried in vacuo. Yield 1.22g (3.44mmol, 86%). 

Naphthalene(tricarbonyl)manganese(I) tetrafluoroborate11 is a pale yellow solid (mp 108°C decomp.). It is best kept under inert atmosphere due to its moisture sensitivity. It dissolves readily in CH2C12 but is insoluble in ether and aromatic or aliphatic hydrocarbons. As a MTT reagent, the naphthalene complex undergoes arene substitution faster than the acenaphthene(tricarbonyl)manganese(I) analogue. 

A 30-mL pressure tube was flame dried under nitrogen and charged with [Mn(r 6-Ci2H10)(CO)3]BF4 (0.21 g, 0.55 mmol) and (V,iV-dimethylaniline (1.40 mL, 1.10 mmol) dissolved in 20 mL dichloromethane. /V,/V- D i met h y I an i I i ne was dried prior to use with 4 A molecular sieves. The tube was sealed, heated in a silicon oil bath at 75°C for 3 h, and then cooled to room temperature. After evaporation to ca. 5 mL, this solution was added slowly to 100 mL of diethyl ether through a plug of Celite. The light yellow solid was filtered off and washed three times with 10 mL aliquots of diethyl ether. The isolated yield of [Mn(Ti6-C6H5NMe2)(CO)3]BF4 was 0.18 g (0.52 mmol, 94%). 

Auffrant, D. Prim, F. Rose-Munch, E. Rose, S. Schouteeten, and J. Vaissermann, Organometallics 22, 1898 (2003). 

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