Nucleophilic Addition to Carbyne Complexes

Experimental Procedure 3.1.4. Preparation of a Molybdenum Vinylidene Complex from a Carbyne Complex Tetrabutylanunoniuih Cyano(ethoxycarbonyl) vinylidene (dicarbonyl) hydro-tris(3,5-dimethyl-1 -pyrazblyl)borato molybdenum [526] [37] pp 151 and 188 

Sodium hydride (0.48 g of a 60% dispersion in paraffin, 12.0 mmol) is added to a stirred solution of ethyl cyanoacetate (1.36 g, 12.0 mmol) in THF (100 mL) at 0°C, followed by addition of solid Tp (CO)2Mo=CCl (2.00g, 4.03 mmol). The resulting mixture is heated under reflux for 24 h, left to cool to room temperature, and treated with solid tetrabutylammonium bromide (1.29 g, 6.14 mmol). Water is added and the mixture extracted with dichloromethane. The combined extracts are washed with water, dried over magnesium sulfate, and concentrated to small volume under vacuum. Treatment of the residue with diethyl ether leads to precipitation of 2.94 g (quant.) of the title compound as a yellow, air-stable solid. NMR (CDCI3) 5 12.57, 13.64, 14.78, 14.94, 16.00, 19.65, 23.96, 58.64, 58.72, 86.89, 105.00, 105.58,124.00, 143.40,143.88, 151.04, 151.75, 171.60, 229.31, 300.00. 

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