Background:
Recently, organic synthesis using ionic liquids (ILs) via green approach has
attracted considerable attention to address the problem associated with environmental pollution.
Magnetization of ILs provides added advantages of separation by external magnet. This can be accomplished
by incorporation of high-spin iron(III) in the form of tetrachloro or tetrabromoferrate(
III). Thus, synthesis of novel magnetically separable ILs for organic transformations is highly
desirable.
Results:
[AcMIm]FeCl4 ionic liquid showed excellent catalytic activity in the one pot threecomponent
synthesis tetrahydrobenzo[b]pyran derivatives at room temperature in excellent yields
(94-98 %) within short reaction time (15-20 min.). The ILs were recovered and reused for at least six
times with the minimum loss of catalytic activity.
Methods:
Here, we have demonstrated the excellent catalytic activity of acid functionalized magnetic
Ils, [AcMIm]FeCl4 in one-pot multicomponent reactions for the synthesis of biologically important
tetrahydrobenzo[b]pyran derivatives.
Conclusion:
A facile and convenient methodology has been developed for the synthesis of bio-active
tetrahydrobenzo[b]pyran derivatives using [AcMIm]FeCl4 ionic liquid as an sufficient and reusable
catalyst under environment-benign conditions.
Improvement in nanocomposite host (nanocavity of dealuminated zeolite Y)-guest (12-molybdophosphoric acid) catalytic activity and its application to the one-pot three-component synthesis of tetrahydrobenzo[ b ]pyrans