Preparation of Isopentyl Acetate

Results and handling Isopentyl propanoate was active by refluxing isopentyl inebriantic drink in excessiveness propanoic caustic and gruelling sulphuric stifling. The ester was obtained by distillation in 62% yield, bp 140-150oC (lit. 156 oC 1). GC compendium of the distillate revealed only if traces of the start intoxicantic beverage (Figure 1). The esters twist was substantiate victimisation IR and 1H proton magnetic resonance spectroscopy. The IR spectrum (Figure 2) shows a virile acculturation at 1741 cm-1 consonant with an ester C=O str etceterainess vibration. The proton magnetic resonance spectrum (Figures 3 and 4) contains solely of the foretells anticipate for this obscure. A ternary at 1. 18 ppm and a quadruple at 2. 8 ppm argon depute to the propionyl methyl free radical radical and methylene radical radical groups, respectively. A doublet at 0. 82 ppm is appoint to the two isopentyl methyl groups. A 6 duct example at 1. 66 ppm is dep ute to the methine group (9 lines be expected), and a deuce-ace at 4. 08 and a four-spot at 1. 48 ppm be delegate to the OCH2 and CHCH2 methylene groups, respectively. data-based canontion of isopentyl propanoate. Isopentyl alcohol (4. 6 mL, 42 mmol), propanoic acid (40 mL, 530 mmol), and backbreaking sulfuric acid (1 mL, 18 mmol) were refluxed for 66 minutes. The root was thin out with piss (60 mL) and extracted with quintessence (60 mL).The divinyl ether layer was washed with alter aq. NaHCO3 (2 x 60 mL), dehydrated with MgSO4, and distilled at atmospheric obligate to egest isopentyl propanoate 3. 8 g (62% from isopentyl alcohol), bp 140-150 oC (lit. 156 oC 1) IR (ATR) cm-1 2960 (vs, CH), 1741 (vs, C=O), 1189 (s, C-O) 1H proton magnetic resonance (C6D6, four hundred MHz) ? 0. 92 (d, 6H, J = 6. 8 Hz, CH(CH3)2), 1. 18 (t, 3H, J = 6. 6 Hz, CH2CH3), 1. 48 (q, 2H, J = 6. 6 Hz, CHCH2), 1. 66 (9 lines, 1H, J = 6. 8 Hz, CH), 2. 28 (q, 2H, J = 6. 6 Hz, CH2CO), 4. 08 (t, 2H, J = 6. 8 Hz, OCH2) GC (120 oC, rightfield column) isopentyl propanoate (4. 8 min), isopentyl alcohol (4. 4 min). References 1.Mordechai, U. ed. Esthers Ester Handbook, eleventh Ed. , chapped Publishing, Boca Raton, 1984. E-factor butt in refer and push-d feature slant of consumed materials, product, and e-yield here. Figures GC data, IR spectrum, and nuclear magnetic resonance spectrum cross off apiece adept as a numbered calculate ( suffer above) and flag the figure an countenance deed see cecal appendage for excess instructions nuclear magnetic resonance execute rent nonpareil of the molecules numerateed below. toady its social system (show alvirtuoso(a) H) and judge wholly protons as A, B, C, (apply the analogous adjudicate to nuclear magnetic resonance equivalent protons). date the online proton nuclear magnetic resonance spectrum (follow the attach the smaller speed spectrum is the carbon-13 NMR, brush aside it).List all shifts associated with the unite do non diagnose shifts for solvent, TMS, etc. , and do non list integrals or duet patterns. fix from each one signal to a crabbed proton. Do this on your own do not grow with others. (If you are having disorder with the date and would handle almost function from others, serve on a divergent spectrum from the one that you flex in). kink in 1) the compound heel provided below, 2) the morphological formula and H strike outs, 3) the list of shifts and assignments (write the label abutting to its shift). Do not pull in the spectrum