Having -c(=x)-, Wherein X Is Chalcogen, Bonded Directly To The Five Membered Hetero Ring (e.g., Pyrrole Carbonyl Halides, Pyrrole Carboxaldehyde, Etc.) Patents (Class 548/530)
The -c(=x)- is part of a -c(=x)x- group, wherein the x's are the same or diverse chalcogens (e.g., pyrrole-3-carboxylic acid, etc.) (Class 548/531)
Acyclic nitrogen bonded directly to the -c(=x)- (e.g., 4,5-dihalopyrrole -2 carboxamides, etc.) (Class 548/537)
Carbocyclic ring bonded directly to the -c(=x)- (e.g., 3-benzoyl pyrrolidine, etc.) (Class 548/539)
Acyclic carbon bonded directly to the -c(=x)- (e.g., n-oleoylpyrrolidine, etc.) (Class 548/540)
  • Preparation of .alpha.-ketocarboxylic acid N-tert.-butylamides
    Patent number: 4345100
    Abstract: A process for the preparation of an .alpha.-ketocarboxylic acid N-tert.-butylamide of the formulaR--CO--CO--NH--C(CH.sub.3).sub.3in whichR is an aliphatic radical with up to 8 carbon atoms, a cycloalkyl radical with 3 to 6 carbon atoms, a phenyl or naphthyl radical or a heterocyclic radical,comprising reacting an acyl cyanide of the formulaR--CO--CNwith tert.-butyl methyl ether of the formula(CH.sub.3).sub.3 C--O--CH.sub.3at a temperature between about 0.degree. and 80.degree. C. in the presence of an acid which is capable of activating the ether of formula (III) under the reaction conditions to give a tert.-butyl carbonium ion, and then hydrolyzing the reaction mixture. Advantageously the acyl cyanide is pivaloyl cyanide or benzoyl cyanide and is reacted with an approximately equimolar amount of the ether in the presence of about 1.1 to 1.5 times the molar amount of concentrated sulphuric acid as the activating acid. The products are useful as intermediates in the synthesis of known herbicides.
    Type: Grant
    Filed: January 2, 1981
    Date of Patent: August 17, 1982
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gerhard Bonse, Heinz U. Blank