Download (4Mb) - Etheses - Saurashtra University

Part-IResults and DiscussionOOON 2 H 4. H 2 ONHNH 2NH 25 6NH 2OO180 o COO7ONNH 2NOScheme-11IxivO3.1.2.c Synthesis of methyl-2-amino-4,5-dimethoxybenzoate 30 (Ixv)Synthesis of methyl-2-amino-4,5-dimethoxybenzoate was carried out through a series offollowing steps. The synthesis starts with o-methylation of vanillin 8, with dimethylsulphate in presence of aq. KOH. In the next step, selective nitration of veratraldehyde 9under controlled conditions was carried out using fuming nitric acid at 0 o C to get 3,4-dimethoxy-6-nitrobenzaldehyde/6-nitroveratraldehyde 10. The 3,4-dimethoxy-6-nitrobezoicacid 11 was prepared by the oxidation of the aldehyde group of 6-nitroveratraldehyde using potassium permanganate as a oxidizing agent. The next stepinvolves the esterification of the benzoic acid by passing dry HCl gas in methanol to getmethyl 4,5-dimethoxy-2-nitrobenzoate 12. The next step involved the reduction of thenitro group with the use of iron powder (activated 80#mesh) and catalytic amount ofconc. HCl in ethanol at 80 o C to get target compound, 2-animo-4,5-dimethoxymethylbenzoate Ixv (Scheme-12).73