Wolff-Kishner reaction

This reaction is discussed extensively in an eadier review (41). In the Huang-Minlon modification of the Wolff-Kishner reaction, a high boiling solvent such as diethylene glycol is used to achieve the required high temperatures (180—210°C) without the use of pressure equipment (42). The base is generally alkaU hydroxide or an alkoxide (43). 

Nucleophilic Addition of Hydrazine The Wolff-Kishner Reaction 715... 

A useful variant of the imine-forming reaction just discussed involves the treatment of an aldehyde or ketone with hydrazine, H2NNH2, in the presence of KOH. Called the Wolff-Kishner reaction, the process is a useful and genera method for converting an aldehyde or ketone into an alkane, r2c=o —> R2CH2. 

Schiff base, 710 Wittig reaction, 720 Wolff—Kishner reaction, 715 yiide, 720... 

Wolff-Kishner reaction (Section 19.9) The conversion of an aldehyde or ketone into an alkane by reaction with hydrazine and base. 

Sandmeyer reaction, 943 saponification. 809-810 SN1 reaction, 373-375 Sn2 reaction, 363-364 Stork enamine reaction, 897-898 transamination, 1167 Williamson ether synthesis, 655 Wittig reaction, 720-721 Wolff-Kishner reaction, 715-716 Meerwein-Ponndorf-Verley reaction, 746... 

The first step in the mechanism of the Wolff-Kishner reaction consists of formation of the hydrazone (16-19). 

The reduction of tosylhydrazones by LiAlH4 or NaBH4 also converts carbonyl groups to methylene.277 It is believed that a diimide is involved, as in the Wolff-Kishner reaction. 

Reduction of the carbonyl group by Wolff-Kishner reaction gives intermediate 52.Treatment of that compound with butyl lithium gives the corresponding... 

Hydrogenolysis of an aldehyde or ketone carbonyl to >CH2 is an important organic transformation, and classical procedures such as the Clemmenson and Wolff-Kishner reactions have limitations (24, 25) heterogeneous catalytic systems and several two-step procedures are also known (1, 24, 26). Our observation of this conversion in what is essentially a 2-phase medium... 

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. 

The rearrangement of hexahydroazocino [4,3-1 ] indole 101 into pyrrolo[3,2-flj-carbazole 102 under Wolff-Kishner reaction conditions is also described in the publication (Scheme 28 84H(22)561). The reaction is a special case of cleavage of compounds related to gramine. 

Wittig reaction of azocine 214 with triphenylmethylenphosphane gives methylene derivative 215. In contrast, under Wolff-Kishner reaction conditions 214 was transformed into azocine 216a. Catalytic hydrogenation of the methylene... 

Willgerodt reaction, 3, 2 Wittig reaction, 14, 3 31 [2,3]-Wittig rearrangement, 46, 2 Wolff-Kishner reaction, 4, 8... 

Xhe transformation of the carbonyl group to methylene in ketoamine 15 (to yield 2) proceeds by means of the Wolff-Kishner reaction (59AP143). 

In the thiophene series a Wolff-Kishner reaction on the 3-aroyl compound 379, in addition to the expected reduction product, affords the pyrazole 381. A typical rearrangement of the hydrazone 380, followed... 

Scheme 15. Reaction conditions i, CH2O, Et2NH ii, EtNH2 iii, CH2=CHCOOEt iv, Na v, Wolff-Kishner reaction.

L. F. and M. Ficscr, Harvard University, Cambridge, MA. hllp //www. harvard.edu/. Reforwalsky Reaction Willgerodt Reaction and Wolff-Kishner Reaction... 

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