title: Highly stereoselective, one-pot synthesis of azetidines and 2,4-dioxo-1,3-diazabicyclo[3.2.0] compounds mediated by I2.
abstract: We report here a convenient method to construct polysubstituted azetidines and 2,4-dioxo-1,3-diazabicyclo[3.2.0] compounds with high stereoselectivities in a one-pot reaction mediated by I2. The tetramethylguanidine (TMG)/I2-mediated formal [2 + 2] cycloaddition reaction of α-amidomalonate 1 with enones 2 affords functionalized azetidine derivatives 4 in moderate to good yields with high diastereoselectivity. When the α-ureidomalonate 5 is used instead of 1, 2,4-dioxo-1,3-diazabicyclo[3.2.0]heptanes 8 and 2,4-dioxo-1,3-diazabicyclo[3.2.0]heptenes 9 can be prepared selectively through the control of solvent and temperature. 2,4-Dioxo-1,3-diazabicyclo[3.2.0]heptanes 8 can further undergo ring-opening reactions with different nucleophilic reagents to afford the corresponding polyfunctionalized azetidine derivatives 13-16 with high steroselectivities.
authors.affiliation: School of Petrochemical Engineering, Changzhou University, Changzhou 213164, People's Republic of China. estally898@yahoo.com.cn
authors.forename: Chun-Bao
authors.initials: CB
authors.lastname: Miao
authors.forename: Chun-Ping
authors.initials: CP
authors.lastname: Dong
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Wen-Long
authors.initials: WL
authors.lastname: Ren
authors.forename: Qi
authors.initials: Q
authors.lastname: Meng
authors.forename: Xiao-Qiang
authors.initials: XQ
authors.lastname: Sun
authors.forename: Hai-Tao
authors.initials: HT
authors.lastname: Yang
mesh_terms: D053961:Azabicyclo Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D001384:Azetidines / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D061565:Cycloaddition Reaction; D007455:Iodine / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D053961:Azabicyclo Compounds; D001384:Azetidines; D007455:Iodine