Trimethoxybenzaldehyde (TMB) was hydrogenated over Pd/C in H 2-AcOH,in H 2-MeOH and in NH 2NH 2-PhMe system respectively.In Pd/C-TMB-H 2-AcOH system,TMB was reduced into 3,4,5-trimethoxytoluene (TMT) via 3,4,5-trimeth...Trimethoxybenzaldehyde (TMB) was hydrogenated over Pd/C in H 2-AcOH,in H 2-MeOH and in NH 2NH 2-PhMe system respectively.In Pd/C-TMB-H 2-AcOH system,TMB was reduced into 3,4,5-trimethoxytoluene (TMT) via 3,4,5-trimethoxybenzyl acetate and (1′-hydroxy)ethyl (3,4,5-trimethoxy)benzyl ether.In Pd/C-TMB-H 2-MeOH system,TMB was reduced into TMT via 3,4,5-trimethoxybenzyl alcohol,methyl(3,4,5-trimethoxy)benzyl ether and bis(3,4,5-trimethoxy)benzyl ether.In Pd/C-TMB-NH 2NH 2-PhMe system,TMB was reduced into TMT directly with mild manner and higher selectivity.展开更多
3,4,5-Trimethoxybenzaldehyde was synthesized from p-cresol in an overall yield of 64 5%. p-Cresol was at first brominated and hydrolyzed to give 3,5-dibromo-4-hydroxybenzal-dehyde, which was methoxylated by methanolic...3,4,5-Trimethoxybenzaldehyde was synthesized from p-cresol in an overall yield of 64 5%. p-Cresol was at first brominated and hydrolyzed to give 3,5-dibromo-4-hydroxybenzal-dehyde, which was methoxylated by methanolic sodium methoxide in the presence of cuprous chloride and dimethylformamide(DMF) at 125 ℃(ca. 0 5 MPa) to provide sodium phenolate of 3,5-dimethoxy-4-hydroxybenzaldehyde, from which 3,4,5-trimethoxybenzaldehyde was obtained by methylation directly with dimethyl sulfate in aqueous sodium hydroxide. "One-pot" method was used in the synthesis starting from economical, convenient and environmental awareness.展开更多
文摘Trimethoxybenzaldehyde (TMB) was hydrogenated over Pd/C in H 2-AcOH,in H 2-MeOH and in NH 2NH 2-PhMe system respectively.In Pd/C-TMB-H 2-AcOH system,TMB was reduced into 3,4,5-trimethoxytoluene (TMT) via 3,4,5-trimethoxybenzyl acetate and (1′-hydroxy)ethyl (3,4,5-trimethoxy)benzyl ether.In Pd/C-TMB-H 2-MeOH system,TMB was reduced into TMT via 3,4,5-trimethoxybenzyl alcohol,methyl(3,4,5-trimethoxy)benzyl ether and bis(3,4,5-trimethoxy)benzyl ether.In Pd/C-TMB-NH 2NH 2-PhMe system,TMB was reduced into TMT directly with mild manner and higher selectivity.
文摘3,4,5-Trimethoxybenzaldehyde was synthesized from p-cresol in an overall yield of 64 5%. p-Cresol was at first brominated and hydrolyzed to give 3,5-dibromo-4-hydroxybenzal-dehyde, which was methoxylated by methanolic sodium methoxide in the presence of cuprous chloride and dimethylformamide(DMF) at 125 ℃(ca. 0 5 MPa) to provide sodium phenolate of 3,5-dimethoxy-4-hydroxybenzaldehyde, from which 3,4,5-trimethoxybenzaldehyde was obtained by methylation directly with dimethyl sulfate in aqueous sodium hydroxide. "One-pot" method was used in the synthesis starting from economical, convenient and environmental awareness.
