| 摘要 |
<p>The regioselective synthesis of 1-alkyl-haloalkylpyrazole-4-carboxylic acid derivatives (I) comprises cyclization of 2.3-disubstituted acrylic acid derivatives (II) with hydrazines (III) in the presence of carbonyl derivatives. Regioselective synthesis of 1-alkyl-3-haloalkylpyrazole-4-carboxylic acid derivatives of formula (I) comprises reaction of 2-acylated acrylic acid derivatives of formula (II) with N-alkylhydrazines of formula H 2NNHR 1(III) in the presence of a compound of formula R 7C(M)R 8(IV). R 1= 1-12C alkyl, 3-8C cycloalkyl, 2-12C alkenyl, 2-12C alkynyl, 6-8C aryl or 7-19C arylalkyl or alkylaryl (all optionally substituted by one or more R', X, OR', SR'N(R') 2, Si(R') 3, COOR', C(O)R', CN or C(O)N(R') 2); R'= H or 1-12C alkyl; R 2= 1-4C alkyl optionally substituted by 1-3 halogen selected from F, Cl or Br or by one CF 3; Y = C(O)OR 3, CN or C(O)NR 4R 5; R 3-R 5= H, 1-12C alkyl, 3-8C cycloalkyl, 2-12C alkenyl, 2-12C alkynyl, 6-8C aryl or 7-19C arylalkyl or alkylaryl (all optionally substituted by one or more R', X, OR', SR'N(R') 2, Si(R') 3, COOR', C(O)R', CN or C(O)N(R') 2); or NR 4R 5= 5 or 6 membered ring; Z 1, Z 2= O or S; R 6= 1-12C alkyl, 3-8C cycloalkyl, 2-12C alkenyl, 2-12C alkynyl, 6-8C aryl or 7-19C arylalkyl or alkylaryl (all optionally substituted by one or more R', X, OR', SR'N(R') 2, Si(R') 3, COOR', C(O)R', CN or C(O)N(R') 2); R 7, R 8= H, 1-12C alkyl, 3-8C cycloalkyl, 6-18C aryl or 7-19C arylalkyl or alkylaryl; and M = O, S, Se, NH, NR'or OR'(sic). [Image].</p> |
