Herein we report a convenient and efficient synthesis of 2-Arylbenzoxazole from the Schiff’s bases of 2-Aminophenol, 3, 5-Diarylisoxazole from α, β-unsaturated ketoxime and 1,3,5-Triarylpyrazole from 2-pyrazoline a...Herein we report a convenient and efficient synthesis of 2-Arylbenzoxazole from the Schiff’s bases of 2-Aminophenol, 3, 5-Diarylisoxazole from α, β-unsaturated ketoxime and 1,3,5-Triarylpyrazole from 2-pyrazoline and N-Arylhydrazone by using milder, less toxic and less expensive-NBS-SiO2, KMnO4-Al2O3, PCC-SiO2 and ACC-Al2O3 as solid-supported oxidizing agents at room temperature. Within the framework of Green Chemistry, the use of solid supported reagents has many advantages such as 1) they are easy to remove from reactions by filtration 2) excess reagents can be used to drive the reaction without introducing any difficulties in purification 3) such solid-supported reagents react differently, mostly more selectively, than their unbound counterparts and 4) toxic, noxious and explosive chemicals are handled more safely when contained on solid support.展开更多
The title compound of PhCH_3C_3HN_2 (O )C (O) (CH_2) _3C [N (CH_2 )_4 NH_2]C_3HN_2 (O)CH_3Ph (L), a new Schiff-base containing diketone, has been synthesized. Its crystal structure has been determined by X-ray diffrac...The title compound of PhCH_3C_3HN_2 (O )C (O) (CH_2) _3C [N (CH_2 )_4 NH_2]C_3HN_2 (O)CH_3Ph (L), a new Schiff-base containing diketone, has been synthesized. Its crystal structure has been determined by X-ray diffraction analysis. The crystal, C_(30)H_(41)N_6O_(5.5) (L·0. 5C_2H_5OH·2H_2O) , is triclinic, space group P1 ,a=11.544 (1) , b=11. 723(5) , c=12. 344(2) A , a=80. 61(2) . β=84. 17(1) ,γ=78. 80(2)°.V=1612. 6(9) A￣3, M_r=1147. 40, Z=2, D_x= 1. 18 g/cm￣3 . μ=0. 77 cm-1, F(000) = 614. The final agreement factor R=0. 079 for 1828 independent reflections with I≥ 3σ(I) considered to be observed. L contains three functional groups:β-diketone,β-ketoimine(Schiff-base) and NH_2. The β-diketone group has partially delocalized. The pyrazoline plane is not coplanar with its connected phenyl plane. The big πbond is not extended between these planes. There are one ethanol and four water molecules in the crystal. Intermolecular hydrogen bonds may exist between C=O and H_2O. NH_2 and H_2O, H_2O and EtOH, or H_2O and H_2O.展开更多
文摘Herein we report a convenient and efficient synthesis of 2-Arylbenzoxazole from the Schiff’s bases of 2-Aminophenol, 3, 5-Diarylisoxazole from α, β-unsaturated ketoxime and 1,3,5-Triarylpyrazole from 2-pyrazoline and N-Arylhydrazone by using milder, less toxic and less expensive-NBS-SiO2, KMnO4-Al2O3, PCC-SiO2 and ACC-Al2O3 as solid-supported oxidizing agents at room temperature. Within the framework of Green Chemistry, the use of solid supported reagents has many advantages such as 1) they are easy to remove from reactions by filtration 2) excess reagents can be used to drive the reaction without introducing any difficulties in purification 3) such solid-supported reagents react differently, mostly more selectively, than their unbound counterparts and 4) toxic, noxious and explosive chemicals are handled more safely when contained on solid support.
文摘The title compound of PhCH_3C_3HN_2 (O )C (O) (CH_2) _3C [N (CH_2 )_4 NH_2]C_3HN_2 (O)CH_3Ph (L), a new Schiff-base containing diketone, has been synthesized. Its crystal structure has been determined by X-ray diffraction analysis. The crystal, C_(30)H_(41)N_6O_(5.5) (L·0. 5C_2H_5OH·2H_2O) , is triclinic, space group P1 ,a=11.544 (1) , b=11. 723(5) , c=12. 344(2) A , a=80. 61(2) . β=84. 17(1) ,γ=78. 80(2)°.V=1612. 6(9) A￣3, M_r=1147. 40, Z=2, D_x= 1. 18 g/cm￣3 . μ=0. 77 cm-1, F(000) = 614. The final agreement factor R=0. 079 for 1828 independent reflections with I≥ 3σ(I) considered to be observed. L contains three functional groups:β-diketone,β-ketoimine(Schiff-base) and NH_2. The β-diketone group has partially delocalized. The pyrazoline plane is not coplanar with its connected phenyl plane. The big πbond is not extended between these planes. There are one ethanol and four water molecules in the crystal. Intermolecular hydrogen bonds may exist between C=O and H_2O. NH_2 and H_2O, H_2O and EtOH, or H_2O and H_2O.
