DERIVATIVES OF BIPHENYL 231 compounds or N-nitrosoacetyl derivatives have been prepared and some of the compounds which have been used for coupling. It is apparent that, by the proper .combination of reagents, derivatives of biphenyl, the ter-phenyls, phenylnaphthalenes, phenylthiophenes, and phenylpyridines can be prepared. With the diazohydroxides the yields usually lie between 15 and 35%, although in some instances they are much lower; with the nitrosoacetyl derivatives the yields are generally higher, lying between 40 and 70%. In some reactions in which the diazohydroxide fails to give the desired product, the nitrosoacetyl derivative may give it. Moreover, the modi-fications, such as the use of sodium acetate or the stabilized diazonium salts, occasionally serve to improve the yield in the diazo reaction. Even when the yields are low, these methods are often the only ones available for preparing substances of definite structure for purposes of identifica-tion. A limitation of both methods is that the second component must be
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This note was uploaded on 11/20/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.