Pyrazole, 3,5-dimethyl-, complexes with tungsten

C5H8N2, Pyrazole, 3,5-dimethyl-, complexes with tungsten, 33 219 C6H8N2O2, Catechol, 4,5-diamino-, 33 112 C6HgBrN202, Benzene, l,2-dihydroxy-4,5-diamino-, hydrobromide, 33 115 C8H12N2O2, Benzene, l,2-dimethoxy-4,5-diamino-, 33 115... 

When methylene chloride was used as a solvent, it was found that 28 are obtained in minor amounts, while the dominating product is the -coordinated chloro-carbyne species [(> -Tp )Mo(CO)2(=CCl)], whose yield increases abruptly with substitution in the pyrazol-l-yl fragments (3-methyl-, 3,4,5-trimethyl-, and 3,5-dimethyl-4-chloro derivatives) [90AX(C)59,95JCS(D) 1709]. The tungsten analog can be prepared similarly. The chlorocarbyne molybdenum complex follows also from the reaction of the parent anion with triphenylsulfonium cation but conducted in dichloromethane. The bromo- and iodocarbyne derivatives are made similarly. 

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