Huang Minion modification

Method B (Huang - Minion modification of Wolff - Kishner reduction)... 

This mixture is the Huang Minion modification of the Wolff Kishner reaction. In the editor s experience it often leaps from the flask with sudden gas evolution. In addition to the expected nitrogen, at the operating temperature of around 200°C it is uncomfortably near the temperature of hydrogen evolution from glycol decomposition. The reduction proceeds much cooler in dimethyl sulfoxide or some of the alkoxyethanols as solvent. 

Example 1, Huang Minion modification, with loss of ethylene here ... 

Huang Minion modification of the Wolff-Kishner reduction. A mixture of 2-pivalyl-l,3-indandione and diethylene glycol treated with hydrazine hydrate, gradually heated during 1 hr. to 150° in an open flask, excess KOH added, the temp, raised to 200° and kept there for 1 hr. l,4-dihydro-3-tert-butylindeno-[l,2-c]pyrazole. Y 91.9%. F. e., also isolation of intermediates, s. R. A. Braun and W. A. Mosher, Am. Soc. 80, 4919 (1958). 

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