title: Regioselective Synthesis of Substituted 4-Alkylamino and 4-Arylaminophthalazin-1(2H)-ones.
abstract: An efficient regioselective synthesis of substituted 4-alkylamino and 4-arylaminophthalazin-1(1H)-ones 5 is described. This new method features the formation of substituted phthalazin-1(1H)-ones 3 by the reaction of 2-formylbenzoic acids 1 or 3-hydroxyisobenzofuran-1(3H)-ones 2 with hydrazine to generate phthalazin-1(2H)-ones 3. Subsequent regioselective bromination of phthalazin-1(2H)-ones 3 with benzyltrimethylammonium tribromide (BTMA-Br3) followed by mixed copper-copper oxide-catalyzed amination of 4-bromophthalazin-1(2H)-ones 4 with primary amines generates aminophthalazin-1(2H)-ones in good overall yields.
authors.affiliation: Discovery Chemistry, Research and Development, Bristol-Myers Squibb Company , PO Box 4000, Princeton, New Jersey 08543-4000, United States.
authors.forename: Subramaniam
authors.initials: S
authors.lastname: Krishnananthan
authors.affiliation: Discovery Chemistry, Research and Development, Bristol-Myers Squibb Company , PO Box 4000, Princeton, New Jersey 08543-4000, United States.
authors.forename: Daniel
authors.initials: D
authors.lastname: Smith
authors.affiliation: Discovery Chemistry, Research and Development, Bristol-Myers Squibb Company , PO Box 4000, Princeton, New Jersey 08543-4000, United States.
authors.forename: Dauh-Rurng
authors.initials: DR
authors.lastname: Wu
authors.affiliation: Discovery Chemistry, Research and Development, Bristol-Myers Squibb Company , PO Box 4000, Princeton, New Jersey 08543-4000, United States.
authors.forename: Shiuhang
authors.initials: S
authors.lastname: Yip
authors.affiliation: Biocon Bristol-Myers Squibb R&D Center , Biocon Park, Bommasandra IV Phase, Jigani Link Road, Bangalore 560099, India.
authors.forename: Prashantha
authors.initials: P
authors.lastname: Gunaga
authors.affiliation: Discovery Chemistry, Research and Development, Bristol-Myers Squibb Company , PO Box 4000, Princeton, New Jersey 08543-4000, United States.
authors.forename: Arvind
authors.initials: A
authors.lastname: Mathur
authors.affiliation: Discovery Chemistry, Research and Development, Bristol-Myers Squibb Company , PO Box 4000, Princeton, New Jersey 08543-4000, United States.
authors.forename: Jianqing
authors.initials: J
authors.lastname: Li