an efficient and environmentally friendly procedure for one-pot synthesis of 13-acetyl-9-methyl-11-ox-8-oxa-10,12-diazatricyclo [7.3.1. ] trideca-2,4,6-triene from salicylaldehyde, acetylaceton and urea via biginelli condensation and intramolecular michael-addition by using magnesium bromide as an expensive and easily available catalyst under solvent-free condition is desired. the structural el...

An efficient and environmentally friendly procedure for one-pot synthesis of 13-acetyl-9-methyl-11-ox-8-oxa-10,12-diazatricyclo [7.3.1. ] trideca-2,4,6-triene from salicylaldehyde, acetylaceton and urea via Biginelli condensation and intramolecular Michael-addition by using magnesium bromide as an expensive and easily available catalyst under solvent-free condition is desired. The structural el...

Silica ferric hydrogensulfate is an efficient heterogeneous catalyst for the cyclization of 2- aminochalcones to the corresponding 2,3-dihydroquinolin- 4(1H)-ones. This intramolecular aza Michael reaction was carried out in high yields using chalcones bearing of electron donating and electron withdrawing groups. The catalyst is reusable without significant decreases in its activity after four t...

Silica ferric hydrogensulfate is an efficient heterogeneous catalyst for the cyclization of 2- aminochalcones to the corresponding 2,3-dihydroquinolin- 4(1H)-ones. This intramolecular aza Michael reaction was carried out in high yields using chalcones bearing of electron donating and electron withdrawing groups. The catalyst is reusable without significant decreases in its activity after four t...

A highly enantio- and diastereoselective intramolecular Stetter reaction has been developed. Subjection of alpha,alpha-disubstituted Michael acceptors to an asymmetric intramolecular Stetter reaction results in a highly enantioselective conjugate addition and a diastereoselective proton transfer. Available evidence suggests the diastereoselective protonation occurs via intramolecular delivery t...

The development of new catalytic asymmetric reactions continues to be a major goal in organic chemistry. Here we report a novel antibody-catalyzed intramolecular Michael addition of aldehydes and ketones to enones. The reaction is enantioselective and diastereoselective with a high ee value and cis/trans ratio. This is the first example of asymmetric intramolecular Michael addition of ketones. ...

The mechanism of the N-heterocyclic carbene (NHC)-catalyzed intramolecular Stetter reaction of salicylaldehyde 1 to yield chromanone 3 has been theoretically studied at the B3LYP/6-31G** level. This NHC-catalyzed reaction takes place through six elementary steps, which involve: (i) formation of the Breslow intermediate IN2; (ii) an intramolecular Michael-Type addition in IN2 to form the new C-C...

The six-pots synthesis of latanoprost has been accomplished with excellent diastereo- and enantioselectivities through an organocatalyst-mediated Michael reaction, a substrate-controlled intramolecular Mukaiyama aldol reaction as key steps.

silica ferric hydrogensulfate is an efficient heterogeneous catalyst for the cyclization of 2- aminochalcones to the corresponding 2,3-dihydroquinolin- 4(1h)-ones. this intramolecular aza michael reaction was carried out in high yields using chalcones bearing of electron donating and electron withdrawing groups. the catalyst is reusable without significant decreases in its activity after four t...

We present a general model for understanding the stereochemical course of intramolecular Michael reactions. We show that the addition of β-ketoester enolates to α,β-unsaturated esters and imides bearing adjacent stereocenters (X, Y = H, Me, OR) leads to high levels of asymmetric induction. Reinforcing and nonreinforcing stereochemical relationships are evaluated from the syn and anti reactant d...