145198-86-3Relevant academic research and scientific papers
Synthesis of 1,3-oxazine derivatives by palladium-catalyzed cycloaddition of vinyloxetanes with heterocumulenes. Completely stereoselective synthesis of bicyclic 1,3-oxazines
Larksarp, Chitchamai,Alper, Howard
, p. 4152 - 4158 (2007/10/03)
1,3-Oxazines were prepared by palladium-phosphine-catalyzed cycloaddition reactions of vinyloxetanes with heterocumulenes. 4-Vinyl-1,3- oxazin-2-imines were obtained in fine yields by the reaction of 2- vinyloxetanes with carbodiimides in THF at rt for 12 h using 1.5 mol % Pd2(dba)3 · CHCl3 and 3 mol % bidentate phosphine ligands (dppe or dppp). When isocyanates were utilized in the reaction, moderate to good yields of 4- vinyl-1,3-oxazin-2-ones were achieved within 1-2 h at rt. Palladium-catalyzed cycloaddition of fused-bicyclic vinyloxetanes with heterocumulenes proceeds in a highly stereoselective fashion affording only the cis-3-aza-1-oxo-9- vinyl[4.4.0]decane derivatives in 43-98% yield.
Regio- and stereoselective synthesis of 1,3-hydroxyl amines via palladium-catalyzed carbonate-carbamate transformation with unique stereoselectivity: Synthesis of 3-amino-4-penten-1-ols
Bando,Harayama,Fukazawa,Shiro,Fugami,Tanaka,Tamaru
, p. 1465 - 1474 (2007/10/02)
The transformation of cyclic carbonates 1 to cyclic carbamates 4 is achieved in the presence of aryl or sulfonyl isocyanate by the catalysis of Pd(0) in high yield and with high structural flexibility. The reaction shows unique stereoselectivity: 3,4-disubstituted carbonates 2, irrespective of the composition of their stereoisomers, provide trans-5 exclusively or predominantly over cis-5. Mixtures of cis- and trans-3,5-disubstituted carbonates 3 furnish either cis-6 or trans-6 in high selectivity depending on the reaction conditions (kinetic or thermodynamic control, respectively). 1H NMR and X-ray structure analyses of 5 and 6 indicate that the stereochemical outcome is governed by an A1,2-strain between N-sulfonyl and C5-vinyl substituents.
Palladium-catalysed Regio- and Stereo-selective Synthesis of Allylic Amines
Tamaru, Yoshinao,Bando, Takashi,Kawamura, Youichi,Okamura, Kazuto,Yoshida, Zen-ichi,Shiro, Motoo
, p. 1498 - 1500 (2007/10/02)
3-Vinyl-2,6-dioxacyclohexan-1-ones 1, by treatment with N-tosyl or N-arylisocyanates and a catalytic amount of Pd0, are converted into N-tosyl- and N-aryl-3-vinyl-2-aza-6-oxacyclohexan-1-ones 2 in good yields and with unique stereoselectivity.
