Tetrakis triphenyl phosphite nickel O

The checkers found that use of a commercially available solution of nickelocene in toluene (ca. 0.27 M) is less desirable, but is admissible with certain modifications of the above procedure. If such a solution is used directly, the amount of (C6H60)3P should be increased to 225 mmoles and a reaction time of 3 days allowed, to give a yield of 53%. Alternatively, the toluene may be vacuum-stripped prior to addition of the triphenyl phosphite. Again, an excess of phosphite (325 mmoles) and a longer reaction time (24 hours) were required, giving a yield of 69%. 

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The hydrocyanation of alk5mes provides a direct method for preparing a,p-unsaturated nitriles such as 67. The reactions proceed at 120 °C in an autoclave with hydrogen cyanide and catal3hic tetrakis(triphenyl phosphite)nickel(O) (Scheme 51). Lower temperatures may be employed if the aUq ne and hydrogen cyanide are added very slowly. The hydrocyanation of dienes and aUcenes (Sections 1.1.1.6 and 1.1.4.5) are much more widely used procedures than the hydrocyanation of alkynes. 

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