c12)  United States Patent  Benkhoff et al.  (IO)  Patent No.:  US 7,144,993 B2  (45)  Date of Patent:  Dec. 5, 2006  (54)  PROCESS FOR THE PREPARATION OF  4-METHYL-7-AMINOQUINOLONES  (75)  Inventors:  Johannes Benkhoff,  Basel (CH);  Bernd Lamatsch,  Riehen (CH)  (73)  Assignee:  Ciba Specialty Chemicals Corp.,  Tarrytown, NY (US)  ( *)  Notice:  Subject to any disclaimer, the term of this  patent is extended or adjusted under 35  U.S.C. 154(b) by 232 days.  (21)  Appl. No.:  10/498,456  (22)  PCT Filed:  Dec. 3, 2002  (86)  PCT No.:  PCT/EP02/13663  § 371 (c)(l),  (2), ( 4) Date:  Jun. 8, 2004  (87)  PCT Pub. No.:  WO03/050089  PCT Pub. Date:  Jun. 19, 2003  (65)  Prior Publication Data  US 2005/0222397 Al  Oct. 6, 2005  (30)  Foreign Application Priority Data  Dec. 11, 2001  (EP)  .................................. 01811206  (51)  Int. Cl.  C07D 215138  (2006.01)  C07C 235/80  (2006.01)  (52)  U.S. Cl.  ......................  534/740;  534/768; 534/771;  546/153; 562/53; 564/200  (58)  Field of Classification Search  ................ 534/740,  534/768, 771; 546/153; 562/53; 564/220  See application file for complete search history.  (56)  References Cited  U.S. PATENT DOCUMENTS  2,152,786  A  *  2,311,054 A  2,688,543  A  *  2,936,306  A  3,119,808  A  3,304,328  A  3,907,494  A  3,933,886  A  4,039,316 A  4,064,131 A  4/1939 Boese, Jr .................... 564/155  2/1943 Kenyon et al .............. 564/200  9/1954 Von Glahn et al .......... 430/146  5/1960 Schmid et al. .............. 260/176  1/1964 Buckley et al. ............. 260/155  2/1967 Pelley ........................ 260/562  9/1975 Saygin ............................ 8/10  1/1976 Saygin ....................... 260/465  8/1977 Perronnet et al .............. 71/118  12/1977 Herkenrath ................. 260/287  FOREIGN PATENT DOCUMENTS  GB  JP  1541460  62-215560  2/1979  *  9/1987  OTHER PUBLICATIONS  R. M. Forbis et al., Journal of the American Chemical Society,  95:15, Jul. 1973, pp. 5003-5013.  The present invention relates to a process for the preparation  of a compound of the general formula (I), which comprises  converting a compound of the general formula  (II), in an  aprotic organic solvent in the presence of a catalytically  active amount of a strong acid (catalyst) or of an agent that  liberates a strong acid or of an ammonium salt of a strong  acid, it also being possible for the catalyst to be part of the  starting material/product, into a compound of formula I,  wherein R 5 , R $^{6 }$and R8 are each independently of the others  a hydrogen atom, a nitro group, a sulfa group, a halogen  atom, a pseudohalogen, a group COOR 1  or CONHR 2  or a  C$_{1}$_$_{8 }$alkyl, C$_{1}$_ 8  alkoxy or aryloxy radical, an amide group, a  thioalkyl or thioaryl radical, an alkyl- or aryl-sulfonyl radi› cal, an alkyl- or aryl-sulfinyl radical, a trifluoromethyl group  or a phosphono group, R 1  and R 2  being a hydrogen atom or  a C$_{1}$ _ 8  alkyl radical or an aryl or aralkyl radical, RIO is a  group ----C(O)CH$_{2}$C(O)CH$_{3 }$ and R$^{11 }$is a hydrogen atom or  an acyl radical, or RIO and R 11  are a group -C(O)CH$_{2}$C  (O)CH$_{3}$ •  The process according to the invention is simple to  perform and results in products of high chemical purity and  high isomeric purity in a high yield  A. Guiotto et al., J. Heterocyclic Chem., vol. 26, Jul. 1989, pp.  917-922.  L. Monti, Gazz. Chim. Ital., vol. 70,(1940), pp. 648-656.  P. Lopez-Alverado et al., Synthesis, (1998), pp. 186-194.  * cited by examiner  Primary Examiner-Fiona  T. Powers  (74)  Attorney, Agent, or Firm-Tyler  A. Stevenson  (57)  ABSTRACT  11 Claims, No Drawings  (II)  (I)  0  US007144993B2 