The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 11, 2007
Filed:
May. 21, 2002
Anita Schnyder, Basel, CH;
Marco Passafaro, Schaffhausen, CH;
Thomas Rapold, Muenchwilen, CH;
Syngenta Crop Protection, Inc., Greensboro, NC (US);
Abstract
Process for the preparation of compounds of formula (I) wherein R is halogen, RORS(O)or (R)NC(X)O; Ris C-Calkly, aryl-C-Calkyl, C-Chaloalkyl or aryl; n is 0, 1, 2 or 3; X is O or S; and Ris hydrogen, C-Calkyl or C-Chaloalkyl, in which process, in a solvent, (1) an aniline derivative of formula (IV) wherein R is as defined above, and Ris C-Calkyl or C-Chaloalkyl, is diazotised in the presence of a mineral acid to form the corresponding diazonium salt of formul (II) wherein R and Rare as defined above, Ais an anion, and m is 1 or 2, (2) the resulting diazonium salt of formula (II) is carbonylated in the presence of a catalyst, CO and optionally a buffer, to form a benzoic acid derivative of formula (III) wherein R and Rare as defined above, and (3) the benzoic acid derivative of formula (III) is then subjected to benzylic lactonisation in the ortho-position alkyl chain Rin the presence of a free-radical initiator and a halogenating agent.