The one-pot three-component reaction of 2-aminobenzothiazole, benzaldehyde derivatives and β-ketoester, β-diketone or malonate derivatives in solvent-free conditions provides the corresponding pyrimido [2,1-b] benzo...The one-pot three-component reaction of 2-aminobenzothiazole, benzaldehyde derivatives and β-ketoester, β-diketone or malonate derivatives in solvent-free conditions provides the corresponding pyrimido [2,1-b] benzothiazole derivatives at 60?C in 60% - 72% yields without using any catalyst in an optimistic time.展开更多
A series of KF/Al2O3 catalyzed Michael-addition reactions between malononitrile and a,b-unsaturated cycloke-tones in DMF solution were studied. At room temperature, 2-cyano-3-aryl-3-(1,2,3,4-tetrahydronaphthalen- 1-on...A series of KF/Al2O3 catalyzed Michael-addition reactions between malononitrile and a,b-unsaturated cycloke-tones in DMF solution were studied. At room temperature, 2-cyano-3-aryl-3-(1,2,3,4-tetrahydronaphthalen- 1-one-2-yl) propionitrile derivatives were synthesized by the reaction between 2-arylmethylidene-1,2,3,4-tetra-hydronaphthalen-1-one and malononitrile. However, if the temperature was increased to 80 ℃, 2-amino-3-cyano-4- aryl-4H-benzo[h]chromene derivatives were obtained in high yields. When the a,b-unsaturated ketones were re-placed by 2,6-biarylmethylidenecyclohexanone or 2,5-biarylmethylidenecyclopentanone, another series of 2-amino- 3-cyano-4H-pyran derivatives was isolated successfully. The structures of the products were confirmed by X-ray diffraction analysis.展开更多
An asymmetric aza-Diels-Alder and O-Michael addition sequence has been developed to construct chiral hy- dropyrano[2,3-b]pyridine derivatives with good yields and excellent stereoselectivity, by starting with N-Ts-l-a...An asymmetric aza-Diels-Alder and O-Michael addition sequence has been developed to construct chiral hy- dropyrano[2,3-b]pyridine derivatives with good yields and excellent stereoselectivity, by starting with N-Ts-l-aza- 1,3-butadienes and aliphatic aldehydes tethered to an α,β-unsaturated ketone motif. A tandem O-Michael addition reaction was completed via acid catalysis.展开更多
文摘The one-pot three-component reaction of 2-aminobenzothiazole, benzaldehyde derivatives and β-ketoester, β-diketone or malonate derivatives in solvent-free conditions provides the corresponding pyrimido [2,1-b] benzothiazole derivatives at 60?C in 60% - 72% yields without using any catalyst in an optimistic time.
基金Project supported by the Foundation of the "urpassing Project"of Jiangsu Province.
文摘A series of KF/Al2O3 catalyzed Michael-addition reactions between malononitrile and a,b-unsaturated cycloke-tones in DMF solution were studied. At room temperature, 2-cyano-3-aryl-3-(1,2,3,4-tetrahydronaphthalen- 1-one-2-yl) propionitrile derivatives were synthesized by the reaction between 2-arylmethylidene-1,2,3,4-tetra-hydronaphthalen-1-one and malononitrile. However, if the temperature was increased to 80 ℃, 2-amino-3-cyano-4- aryl-4H-benzo[h]chromene derivatives were obtained in high yields. When the a,b-unsaturated ketones were re-placed by 2,6-biarylmethylidenecyclohexanone or 2,5-biarylmethylidenecyclopentanone, another series of 2-amino- 3-cyano-4H-pyran derivatives was isolated successfully. The structures of the products were confirmed by X-ray diffraction analysis.
文摘An asymmetric aza-Diels-Alder and O-Michael addition sequence has been developed to construct chiral hy- dropyrano[2,3-b]pyridine derivatives with good yields and excellent stereoselectivity, by starting with N-Ts-l-aza- 1,3-butadienes and aliphatic aldehydes tethered to an α,β-unsaturated ketone motif. A tandem O-Michael addition reaction was completed via acid catalysis.
