A convenient route to polyfunctionalised indeno[ 1,2 - b ]pyran derivatives
摘要:
2-Arylidene-1,3-indanediones undergo facile formal hetero-Diels-Alder cycloadditions with ynamines bearing electron-withdrawing groups yielding polyfunctionalised indeno[1,2-b]pyrans.
Introduction of a clean and promising protocol for the synthesis of β-amino-acrylates and 1,4-benzoheterocycles: an emerging innovation
作者:Garima Choudhary、Rama Krishna Peddinti
DOI:10.1039/c1gc15701a
日期:——
A highly efficient, elegant and simple procedure with exceptionally mild conditions has been proposed for the synthesis of β-amino-acrylate derivatives and an array of biologically and pharmaceutically active benzoheterocycles. The protocol offers a valuable alternative to known methods and will find applications in the field of green synthesis. The regio- and stereo-chemistry of the products were established by IR, NMR and single crystal X-ray analysis.
An efficientsynthesis of various β-enaminoesters has been achieved via Reformatskyreaction with disubstituted formamides as novel electrophiles. The exclusive β-enaminoester E-isomers were obtained in 60–72% yield.
Synthesis of 2-aminofurans and 2-unsubstituted furans via carbenoid-mediated [3 + 2] cycloaddition
作者:Yaojia Jiang、Vanessa Zhong Yue Khong、Emmanuvel Lourdusamy、Cheol-Min Park
DOI:10.1039/c2cc18139h
日期:——
An efficient dual synthetic manifold for 2-aminofurans and 2-unsubstituted furans has been developed. The carbenoid-mediated [3 + 2] cycloaddition of copper carbenoids with enamines provides 2-amino-2,3-dihydrofurans which serve as common intermediates for both 2-aminofurans and 2-unsubstituted furans.
A general, diastereoselective synthesis of functionalised pyrrolidine, indolizidine, pyrrolizidine and its seven-, eight-membered homologues is reported, starting from readily available enamine esters and acetylenedicarboxylate (DMAD).
α-Cyclization of tertiary amines. Part 3. Captodative or push-pull enamines form pyrrolines, pyrrolizidines and their ring homologues with dimethyl acetylenedicarboxylate in a highly diastereoselective reaction
作者:Benoît De Boeck、Shuiping Jiang、Zdenek Janousek、Heinz G. Viehe
DOI:10.1016/s0040-4020(01)85235-2
日期:1994.1
The title one-pot reaction occurs through a sequence of [2+2] cycloaddition, ring opening to dienamines and formation of a 1,5-dipole by [1,6] hydrogen-shift. This intermediate may cyclize or, in sterically suitable cases and at lower temperatures, lead to isolable N-vinyl enamines by proton transfer.