Steric Hyndrance Effects on Esters essays

Steric Hyndrance Effects on Esters essays Electronegative and Steric Hindrance Effects on Synthesized Esters Esters are made when an acid and an alcohol are mixed. The reaction causes the oxygen and hydrogen atoms to pair off, forming H20, leaving the rest of the compound to form the ester. The theory is that if a more electronegative element was added to the compound, it could increase the electronegativity in the whole molecule, and the ester could form more rapidly. The idea is that if you use a 3bromo1propanol alcohol mixed with ethanoic acid, the bromine should create enough electronegativity so that the ester would form with more quantity and speed. This should effect the formation more than steric hindrance because the bromine is attached to the third carbon, hence all the movement from steric hindrance shouldnt cause bulkiness. Bromine is used because it is a very electronegative atom and should act as a catalyst by speeding up the reaction rate. Synthesis of 3-bromopropyl acetate: 3- Bromo-1-propanol(11g, 117mmol) was added to two molar equivalents of ethanoic acid (13.992g, 233.2mmol). 3 drops of H2SO4 was added per every gram of the alcohol. It was refluxed for 30 minutes and allowed to cool overnight. The room temperature mixture was placed into a seperation funnel, where it was rinsed twice with distilled H2O, discarding as much of the aqueous layer as possible. It was then rinsed with 15 to 20 mL of NaHCO3 letting the pressure buildup escape at routine intervals until there was no more excessive pressure. This aqeous layer was tested with lithmus paper and was decided to be neutral. It was rinsed again with distilled H2O, and once again with the NaHCO3. It was then dried over 1.78g of MgSO4. The mixture was distilled and was discovered to have an 82% yield. Density of 1.489715, and a b.p. of 105.5C (literature 8027). NMR (CDCl3,300MgHz) 2.07797ppm (s,3H,CH3), 2. ...