Grignard reagents, bonding hydrolysis

The yields of addition products in reactions of this kind are generally high. The adducts have metal-oxygen bonds that can be broken readily by acid hydrolysis to give the organic product. Grignard reagents seldom add to carbon-carbon multiple bonds (however, see Section 14-12D). 

Exercise 14-33 Grignard reagents, such as CH3Mgl, often add to the triple bond of nitriles, RCssN, to give adducts that, on hydrolysis, yield ketones, RCOCH3. Show the possible steps involved. 

Compounds such as R2SnCl2 and R2SiCl2 have several uses because two reactive Sn-Cl bonds remain that can undergo hydrolysis, reactions with alcohols, and so on. The reactions of Grignard reagents constitute one of the most general synthetic procedures, and they can be used in a wide variety of cases. 

Monoquaternization of rtr-diphosphabicycloalkanes 179, followed by the treatment of the monoquaternary salts 180 with alkyllithium or Grignard reagents to stereoselectively cleave P-P bond, produced rif-disubstituted diphos-phacycloalkanes 68, 181, 182, 63-65, and 183. Di-quaternization of 179, and subsequent hydrolysis and reduction with LiAlH4, gave the trans-isomers of 62 and 64 < 1998J(P 1) 1643 >. 

Several brief preliminary reports in the literature indicate the formation of products from nitric oxide containing nitrogen-nitrogen bonds. Lithium aluminum hydride plus nitric oxide is reported to give rise to hyponitrite ion (17), Grignard reagents (27) and aluminum triethyl (3), when reacted with NO, give rise to intermediates which upon hydrolysis produce nitrosated alkyl-substituted hydroxyl-amines. These materials are reported to be unstable and evidence for their existence is indirect. If these products are indeed formed, the reactions can be easily incorporated into the BNO scheme. 

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