The rates of saponification of some o-substituted ethyl m- and p-aminobenzoates was written by Price, Charles C.;Lincoln, Dwight C.. And the article was included in Journal of the American Chemical Society in 1951.Application In Synthesis of Ethyl 3-amino-4-methylbenzoate This article mentions the following:
Steric inhibition of resonance between a MeN2 group and a C6H6 ring was measured by determining the rates of saponification of 3,4-(Me2N)MeC6H3CO2Et (I) and 3,4-Me(Me2N)C6H3CO2Et (II). The inhibition of resonance by 1 o-Me group markedly affects the elec. influence of the Me2N group in the para or meta position to the reactive ester group, although quantitatively the influence is greater in the para position. A 2nd-order inductive or field effect is necessary to account for such a resonance influence on the meta position. m-H2NC6H4CO2H on methylation yielded the HI salt of trimethyl-m-benzobetaine, which on pyrolysis gave m-Me2NC6H4CO2Me; acid (III), m. 150.5-1.3鎺? Methylation of the amino acid yielded p-Me2NC6H4CO2Me (IV), heavy, white needles, m. 237-8鎺? p-MeC6H4CO2H on nitration and reduction gave 3,4-H2N(Me)C6H3CO2H (V). A slurry of 41.0 g. V in 150 cc. water treated dropwise with 137 g. Me2SO4 in 4 portions, each added in 30 min. (the solution was neutralized with 1 equivalent of concentrated K2CO3 after the addition of each portion), the solution stirred 30 min., treated with NH4OH, extracted with Et2O, the aqueous layer boiled with C, filtered, cooled, barely acidified with AcOH, the acid solution extracted with Et2O, and the extracts evaporated to dryness yielded 14.0 g. I, fine, white needles from Skellysolve L, m. 124.0-6.0鎺? The Et2O layer evaporated, the oil refluxed 1 hr. with 150 cc. 6 N HCl, the solution neutralized with K2CO3, the alk. solution extracted with Et2O (extract discarded), and the aqueous layer treated as above yielded 16 g. I; the combined portions on recrystallization m. 125.6-6.6鎺? o-MeC6H4NHAc on bromination, hydrolysis, and methylation (Me2SO4) yielded 2,4-Me2N-(Br)C6H3Me (VI), b7 105-7鎺? nD20 1.5645. Li (3.1 g.) and 70 cc. Et2O treated dropwise with 42.8 g. VI, the mixture stirred 4 hrs., poured over excess powd. Dry Ice, the Dry Ice evaporated, the mixture treated with water, just acidified with dilute HCl, and extracted with Et2O, the extracts extracted with saturated Na2CO3, the aqueous layer boiled with C, and the filtrate cooled and barely acidified with dilute HCl yielded 8.3 g. II, white scales from hot water containing a little EtOH (monoclinic crystals from Skellysolve L), m. 131.0-1.6鎺? The Et ester of IV m. 63.5-64鎺?(from aqueous EtOH). For the Et esters the b.p./mm and nD20 are: of III, 124.5 鍗?0.3鎺?3.0, 1.5475; of V, 154.6-55鎺?6.0, m. 48.6-50.1鎺? I, 98.0 鍗?0.5鎺?0.8, 1.5270; II, 156.0 鍗?0.3鎺?12, 1.5438. In the experiment, the researchers used many compounds, for example, Ethyl 3-amino-4-methylbenzoate (cas: 41191-92-8Application In Synthesis of Ethyl 3-amino-4-methylbenzoate).
Ethyl 3-amino-4-methylbenzoate (cas: 41191-92-8) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits, including apples, durians, pears, bananas, pineapples, and strawberries. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.Application In Synthesis of Ethyl 3-amino-4-methylbenzoate
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics