The double 1,3-dipolar cycloaddition of allenoates with nitrilimines has been achieved under mild reaction conditions, affording a variety of spirobidihydropyrazoles in moderate to excellent yields with excellent diastereoselectivities. The reaction diastereoselectively constructs double dihydropyrazole moieties and two chiral centers including a spiro carbon center.
The thermal [3 + 2] cycloaddition reaction of phthalazinium dicyanomethanide with various allenoates worked efficiently under mild reaction conditions to give functionalized tetrahydropyrrolo[2,1-a]phthalazine derivatives in good to excellent yields and excellent diastereoselectivities.
在较温和的反应条件下,酞菁双氰胺与各种脲基酸酯的热[3 + 2]环加成反应可有效地产生官能化的四氢吡咯并[2,1- a ]酞嗪衍生物,并具有良好的产率和优异的非对映选择性。
Thermal [3 + 2] cycloaddition of N-iminoquiazoline ylides with allenoates for synthesis of tetrahydropyrazoloquinazoline derivatives
The thermal [3 + 2] cycloaddition reaction of N-iminoquiazoline ylides with allenoates worked efficiently under mild reaction conditions to provide a variety of tetrahydropyrazoloquinazoline derivatives in good to excellent yields and moderate to excellent diastereoselectivities.
Phosphine-Catalyzed [2 + 4] Annulation of Allenoates with Thiazolone-Derived Alkenes: Synthesis of Functionalized 6,7-Dihydro-5<i>H</i>-pyrano[2,3-<i>d</i>]thiazoles
Phosphine-catalyzed [2 + 4] annulation of allenoates with thiazolone-derived alkenes has been achieved under mild conditions, giving biologically important 6,7-dihydro-5H-pyrano[2,3-d]thiazole derivatives in high to excellent yields. With the use of Kwon’s phosphine as the chiral catalyst, optically active products were obtained in good yields with excellent enantioselectivities.
在温和的条件下实现了膦催化的脲基酮衍生的烯醇酸酯的[2 + 4]环化反应,从而以高收率或优异的收率获得了生物学上重要的6,7-二氢-5 H-吡喃并[2,3- d ]噻唑衍生物。 。通过使用Kwon的膦作为手性催化剂,以良好的收率和优异的对映选择性获得了光学活性产物。
Double [3 + 2] cycloaddition of nitrile oxides with allenoates: Synthesis of spirobidihydroisoxazoles
Abstract The double [3 + 2] cycloaddition of allenoates with nitrileoxides is presented. The reaction worked well under mild reaction conditions to give the spirobidihydroisoxazole in moderate to excellent yields with excellent diastereoselectivities. The two dihydroisoxazole rings have been formed via a sequential double [3 + 2] cycloaddition.