References
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- Gupta , K. R. and Tandon , S. G. 1974 . Talanta , 21 : 249 The 4-nitrobenzohydroxamic acids were chosen because of their enhanced acidity and hence, as a consequence, predominant if not exclusive methylation8 of the OH group was anticipated. In the event only O-methyl ether formation was observed. The subsequent selective removal of the nitrobenzoyl group is also an easy process. These O-methyl ethers possess the additional advantage, in contrast to the correspondind trifluoro analogues, of being highly crystalline and stable
- Priyadarshini , U. and Tandon , S. G. 1967 . J. Chem. Eng. Data , 12 : 143
- Lombardi , P. 1990 . Chem Ind. (London) , 708 For large scale methylation with diazomethane, the useful technique described by Lombardi was adapted:
- Shchukin , G. I. and Volodarskii , L. B. 1979 . Izv. Akad. Nauk. SSSR, Ser. Khim. , 1 : 228 The alkylation of N-substituted hydroxamic acid with diazomethane is reported to afford a mixture of nitrone and O-methyl ether:
- CA , 90 152078 c
- Reacylation of the hexane solution with 4-nitrobenzoyl chloride in the presence of NaHCO3 regenerated, in each case, the starting material 2 in yields > 90%.
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