Diazomethane reaction with quinones

Similar waves in the cathodic polarogram were observed by Donnet and Henrich 58) using oxidized carbon black. The wave disappeared after treatment with isobutyronitrile. It was assumed that isobutyro-nitrile gives an addition reaction with quinones. No reaction with this reagent was observed after reduction with hydrogen iodide, after treatment with aniline, or after treatment with diazomethane. The latter finding confirms the assumption by Studebaker et al. 38) that diazomethane is added to the quinones in the carbon black surface. 

In ethereal solution diazomethane can he preserved for a long time. Information about its numerous reactions (with hydrogen cyanide, acetylene, quinone, etc.) can he found in the special literature of the subject. As has already been mentioned, it is an important methylating agent, especially for phenols. With them it reacts in such a way that the two nitrogen atoms are eliminated as elementary nitrogen, and the two valencies which thus become free are occupied by H and OR. 

Diazomethane is capable of addition reactions with double bonds. Pyrazoline rings are formed. Studebaker et al. (38) saw in this reaction an indication of quinone groups ... 

Selective methylation of a.,a a."-trihydroxyanthraquinones. Quinones of this type (e.g. 1) are mono-methylated by reaction with excess diazomethane in CH2CI2. This reaction can be used to convert carminomycinone into daunomycinone (3) in 45% yield. ... 

Kametani s group has applied the diazomethane ring expansion reaction of 3,4-dihydroisoquinoline methiodides to the preparation of isopavines. The carbon insertion reaction with the 3-aryl-3,4-dihydroisoquinoline methiodide 13 supplied a crude aziridinium iodide which upon standing in 6N hydrochloric acid for a week underwent successive ring expansion and closure, probably through the quinone methide 14, to furnish reframidine in 20% yield from the aziridine salt ... 

Aldehydes and ketones can also be converted to epoxides by treatment with a diazoalkane,most commonly diazomethane, but an important side reaction is the formation of an aldehyde or ketone with one more carbon than the starting compound (Reaction 18-9). The reaction can be carried out with many aldehydes, ketones, and quinones. A mechanism that accounts for both products is... 

The iV-methyl nitrone (270) is obtained by reaction of benzo[6]-thiophene-2,3-quinone 3-oxime with diazomethane, or by treating the parent quinone with iV-methylhydroxylamine.632 With O-methyl-hydroxylamine, benzo[6]thiophene-2,3-quinone affords 271.632... 

Diels-Alder reaction to give benzo analogs of 215 (83ZN(B)392), which were also obtained by bromine oxidation of the polycyclic precursors (86CZ455). Quinone 216 was prepared with diazomethane (83ZN(B)392). 

P NMR was used to examine the products from the reaction of both 1 2 and 1 4 benzoquinones with trimethylphosphite (Argy-ropoulos and Zhang 1998). The former formed cyclic trimeth-ylphosphate derivatives of the hydroquinones in a reaction comparable to that with diazomethane, and were hydrolyzed to 2-hydroxyphenyldimethylphosphates. The 1 4 quinone formed 1-methoxy-4-phenyldimethyl phosphate. 

Eistert, B. and Bock, G., Reactions of a-dicarbonyl compounds and quinones with diazoalkanes. II. The reaction of some substituted p-benzoquinones with diazomethane to p-epoxymethylcyclo-... 

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