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A new Wolff-Kishner procedure, involving potassium t-butoxide in toluene, has been used to reduce benzophenone and also two compounds [cholest-4-en-3-one and the a-amino-ketone (I)] that give abnormal products under conventional conditions. THE Wolff-Kishner reaction of hydrazones and semicarbazones is a popular method for reducing aldehydes and ketones to hydrocarbons, but there are numerous reports of the formation of unexpected products. For example, reduction of the carbonyl groups of ap-unsaturated aldehydes and ketones is frequently accompanied by a shift in the position of the double bond.1 In the Wolff-Kishner reaction of many a-amino-ketones and related compounds, an elimination competes with the normal reduction, and in some instances is the predominant reacti0n.~*3 Typical procedures for the Wolff-Kishner reaction involve the use of metal alkoxicles at 180-220" or the use of potassium hydroxide in ethylene glycol at ZOO", and these rather vigorous conditions may be responsible for some of the anomalous reactions. The Wolff-Kishner reaction is usually considered 334 to occur by the following mechanism : B-./-? 0 H6 \ ,c=N-NH, >c-N=NH >CH-N=N-N, + >CH-.r_t >CH,

The reaction of phenoxides with symmetrically substituted diaryliodonium salts provides a general route to substituted diaryl ethers. This procedure and other methods were used to synthesise the phthalimido-ester [VI : R = CH2*CH2*N(CO)2C6H4-o] and the corresponding amino-acid (VII) . DIARYLIODONIUM SALTS are readily attacked at position 1 by nucleophiles,2 and thus show promise as general electrophilic phenylating agents. The reaction with phenoxides proceeds, apparently, by a variation of the SN2 m e c h a n i~m ,~.~ and gives diphenyl ethers :We have studied the reaction further because of our interest in diphenyl ethers as intermediates in the synthesis of bisbenzylisoquinoline alkaloids. Since only a few examples have been r e p~r t e d ,~* * *~ the reactions of simple iodonium salts were examined first, in order to establish a suitable procedure and to determine the scope of the method. The ( I ; R = Me, X = Br) Guaiacol Me OMe H H 64 (I; R = Me, X = Br) Vanillin Me OMe H CHO 63 (I; R = Me, X = Br) Isovanillin Me OMe CHO H 65The amino-acid (VII) is required in the synthesis of bisbenzylisoquinolines, and one scheme devised for its preparation involved the reaction of the phthalimido-phenol (V) with the 4,4'-di(methoxycarbonylmethyl)diphenyliodonium salt (IV) and hydrolysis of the product [VI ; R = CH,*CH,*N(CO),C,H,-01. Oxidative iodination of methyl phenylacetate followed by addition of the appropriate inorganic salt gave the diaryliodonium bromide, chloride, or iodide (IV). Heating the iodide at 160" or refluxing its solution in

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