Patent ID: 8198465

Claim:
A method for preparing a compound of formula (VIII) wherein R 3 is C 1-7 alkyl or C 3-8 cycloalkyl; and R 4 is C 1-7 alkyl, C 2-7 alkenyl, C 3-8 cycloalkyl, phenyl- or naphthyl-C 1-4 alkyl, each unsubstituted or mono-, di-, or tri-substituted by C 1-4 alkyl, O—C 1-4 alkyl, OH, C 1-4 -alkylamino, di-C 1-4 -alkylamino, halogen, and/or trifluoromethyl; and Act is an activating group selected from the group consisting of C 1-10 alkenyloxy-carbonyl, C 6-10 aryl-C 1-6 alkyl, C 1-6 alkyl-carbonyl, C 6-10 aryl-carbonyl, C 1-6 alkoxy-carbonyl, C 6-10 aryl-C 1-6 -alkoxycarbonyl, C 1-6 alkyl-sulfonyl, and C 6-10 aryl-sulfonyl, preferably, C 6-10 aryl-C 1-6 -alkoxycarbonyl, C 1-6 alkoxy-carbonyl, allyloxycarbonyl, and C 6-10 aryl-C 1-6 alkyl; R 1 is halogen, hydroxyl, C 1-6 halogenalkyl, C 1-6 alkoxy-C 1-6 alkyloxy or C 1-6 alkoxy-C 1-6 alkyl; R 2 is halogen, hydroxyl, C 1-4 alkyl, or C 1-4 alkoxy, or a salt thereof; comprising the step of lactam ring opening of the N-activated lactam lactone of formula (VI) or a salt thereof wherein R 3 , R 4 , and Act are as defined above; with a compound of formula (VII) wherein R 1 and R 2 are as defined above, and wherein Y is a metal containing group such as —Li, —MgX, -magnesate, aryl magnesium species, alkyl magnesium species, —MnX, (alkyl) 3 MnLi—, or —CeX 2 wherein X is halogen, such as Cl, I, or Br, more preferably Br.