Agent solvolyzing

As all four of the hydrides can eventually be transferred, there are actually several distinct reducing agents functioning during the course of the reaction.60 Although this somewhat complicates interpretation of rates and stereoselectivity, it does not detract from the synthetic utility of these reagents. Reduction with NaBH4 is usually done in aqueous or alcoholic solution and the alkoxyboranes formed as intermediates are rapidly solvolyzed. 

While screening for p-lactam antibiotics stable to p-lactamases, a strain of Streptomyces lactamdurans was found to contain several such agents which have a 6-a-methoxy group whose electronic and steric properties protect the antibiotic from enzymatic attack. Cephamycin C (29a), one of these substances, is not of commercial value, but side chain exchange has led to much more potent materials. Of the various ways of effecting this transformation, one of the more direct is to react cephamycin C with nitrous acid so that the aliphatic diazo product (29b) decomposes by secondary amide participation giving cyclic iminoether 30. The imino ether moiety solvolyzes more readily than the p-lactam to produce 7-aminocephamycinic... 

The metal—carbon (metal—polymer) bond is strongly polar, and thus easily attacked by solvolyzing agents. Water and alcohols are the most efficient terminators of this kind. 

Pure selenium(IV) oxychloride melts at 10.9 to 11° and boils at 177.2° (744 mm.). It has a high dielectric constant (about 55 at 25°)and is therefore an interesting nonprotonic solvent in which a wide variety of reactions may be caused to take place. The specific conductance of selenium(IV) oxychloride is also high (2.0 X lO" mho at 25°), in which respect it is similar to sulfuric acid, and this property is probably related to the fact that these solvents are powerful solvolyzing agents. It presumably undergoes autoionization in accordance with the equation ... 

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