Ring Transformation of 2‐(Haloalkyl)azetidines into 3,4‐Disubstituted Pyrrolidines and Piperidines.

Abstract

Azetidine derivatives R 0045Ring Transformation of 2-(Haloalkyl)azetidines into 3,4-Disubstituted Pyrrolidines and Piperidines. -The substrates are reduced with chloroalane and the products transformed to cis-substituted alkoxy-pyrrolidines and piperidines. In this context, the possibility of introducing nucleophiles others than halide is demonstrated. -(VAN BRABANDT, W.; VAN LANDEGHEM, R.; DE KIMPE*, N.; Org. Lett. 8 (2006) 6, 1105-1108; Dep. Org. Chem., Fac. Biosci. Eng., Univ. Gent, B-9000 Gent, Belg.; Eng.) -R. Steudel 30-103

Crystal structure of 2-(bromomethyl)-4-(4-chlorophenyl)-1-tosylpyrrolidine, C18H19BrClNO2S2

“…The bromine atom can easily be replaced by other functional groups to generate corresponding products [1][2][3][4][5][6][7]. They have been widely used as broad-spectrum anti-bacterial agents [8], these been reported in the utilize of anti-cancer research [9,10] and also arouse a signi cant pharmacological interest [11].…”

Stereo- and Regioselective Synthesis of 4-Vinylpyrrolidine from N-Tethered Alkyne-Alkenol

“…5 Apart from these, pyrrolidine-based organocatalysts 6 and chiral ligands 7 are also employed in a wide range of organic transformations. Because of their enormous synthetic importance, several efforts have been made toward the synthesis of pyrrolidine such as intramolecular hydroamination of alkenes, 8 aza-Michael reaction, 9 nitro-Mannich/hydroamination cascade reaction, 10 ring transformation of 2-(haloalkyl)azetidines, 11 [4 + 2] cycloaddition reaction of nitroalkenes, 12 [3 + 2] cycloaddition reaction, 13 cyclization of nitrogen-containing acetals and ketals, 14 2,3-dichloro-5,6-dicyano-1,4-benzoquinone-mediated amido cyclization reaction, 15 palladium-catalyzed carboamination reactions of γ-aminoalkenes with aryl and vinylhalides, 16 palladium-17 and platinum-catalyzed 18 coupling reaction of Nsulfonated enynes, and gold-catalyzed intramolecular cyclization of N-tethered alkynes. 19 Lewis acids such as FeCl 3 20 and InCl 3 21 have also been used for cyclization of N-tethered alkyne-alkenol and C-tethered alkyne-allyl bromide, respectively.…”

One-Pot Multicomponent Synthesis of Highly Functionalized Piperidines from Substituted β-Nitrostyrenes, Meldrum’s Acid, Aromatic Aldehydes, and Ammonium Acetate

“…Similarly, other developed approaches included an iridium-catalyzed enantioselective hydrogenation, diphenylprolinol silyl ether mediated Michael reaction and aziridinium ring expansion . D’hoogue and De Kimpe also reported the ring expansion of azetidines to piperidines . In 2003, Hong and co-workers reported a [6 + 3] cycloaddition of azomethine ylides with fulvenes, in which fulvenes served as 6π components, thus leading to the synthesis of racemic piperidine derivatives .…”