Process for preparing biaryl compounds via coupling of an arylamine with an arene
AssigneeBiaschim S.p.A.
InventorsOreste Piccolo, Aldo Belli, Giovanni Villa, Enrico Zen, Attilio Citterio
Life of this patent
Estimating the term…
Abstract
Improvement in the process for preparing biaryl compounds via coupling of an arylamine with an arene in the presence of a nitrite, an acid and copper metal or a derivative thereof; the improvement is consisting in adding to the reaction mixture a trialkylorthoformate. The process may be used for preparing drugs such as Flurbiprofen and Xenbucin or intermediate compounds particularly useful for preparing Flurbiprofen, Flufenisal, Chlordimorin, Xenbucin, Xenysalate, Xenyhexenic acid and the like.
Claims15
In a process for preparing biaryl compounds via coupling of an arylamine with an arene in the presence of a nitrite, an acid and metal copper or a derivative thereof according to the following scheme:
- (R).sub.x ArNH.sub.2 +(R').sub.y Ar'H.fwdarw.(R).sub.x Ar--Ar'(R').sub.y (I)
- wherein
- Ar and Ar' are independently aromatic radicals;
- x and y are independently selected from 0,1,2 and 3;
- R and R' are independently selected from C 1-6 alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, halogen, nitro, cyano, OZ, SZ, COZ, --O--COZ, (NC)m CBp, (AOOC)m--CBp and (NC(AOOC)CBp,
- where
- Z is hydrogen, C 1-6 alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl or aryl;
- m is 1 or 2;
- p is 2 when m is 1 and 1 when m is 2;
- each B is independently selected from hydrogen, C 1-6 alkyl, substituted alkyl, cycloalkyl and substituted cycloalkyl;
- and
- each A is independently selected from hydrogen, C 1-6 alkyl, substituted alkyl, cycloalkyl and trialkylsilyl or, when m is 2, both A may form a cyclic ester;
- the improvement comprising carrying out the reaction in the presence of a trialkylorthoformate.
Dependencies are inferred from the claim text.