Why are cyclic esters easily opened in base, but closes very easily in the presence of acid
Why are cyclic esters easily opened in base, but closes very easily in the presence of...
7-oxo-7-phenylheptanal in the presence of base undergoes a cyclic aldol reaction OH OH
Can someone walk me through this mechanism please. 0) Esters undergo hydrolysis in presence of base to form carboxylate ion and alcohol. Dihydrofuran-2(3H)-one undergoes base hydrolysis in presence of aqueous NaOH gives sodium- 4-hydroxybutanoate. The reaction is as follows: NaOHHO (aqueous) O Na Dihydrofuran-2(3H)-one sodium 4-hydroxybutanoate
3. Cyclic compounds The presence of the ring in all but very large ring cyclic molecules prevents full rotation of the ring atoms. For this reason, stereoisomerism may also occur in cyclic molecules. a) Prepare a model of cyclohexane, CH12. Draw the condensed formula b) Build a model of methylcyclohexane (C;H2a) by replacing one of the hydrogens of cyclohexane with a methyl group. Draw the skeletal formula for methylcyclohexane. c) How many different isomers exist for methylcyclohexane (C-Ha)? d) Start...
Carboxylic acid esters can undergo acid catalyzed hydrolysis, neutral hydrolysis and base catalyzed hydrolysis. Below is a table with three structurally related carboxylic acid esters and the second order reaction rate constants for the acid-catalyzed mechanism (k_A) and the rate constant for the base-catalyzed mechanism (k_B). The difference between the three compounds is mainly the substitution of hydrogen atoms on R_1 with the more electronegative chlorine atoms. a) Explain why there is only a small change in k_A for the...
7-Cyclopentyl-6-oxoheptanal in the presence of base undergoes a cyclic aldol reaction. Complete the mechanism for the following reaction by adding any missing atoms, bonds, charges, nonbonding electron pairs and curved arrows.
12. Why aren't we very worried about the potential presence of B cells that recognize host antigens?
Two species that differ by the presence of a proton are called a) conjugate acid-base pair b) conjugate acid c) conjugate base d) amphoteric molecule
3. Cyclic compounds The presence of the ring in all but very large ring cyclic molecules prevents full rotation of the ring atoms. For this reason, stereoisomerism may also occur in cyclic molecules. a) Prepare a model of cyclohexane, C6H12. Draw the condensed formula. b) Build a model of methylcyclohexane (C7H14) by replacing one of the hydrogens of cyclohexane with a methyl group. Draw the skeletal formula for methylcyclohexane. 2 c) How many different isomers exist for methylcyclohexane (CyH34)? d)...
3. Give a brief explanation why acid chlorides are more reactive than esters in a nucleophilic substitution reaction, like a polymerization. Grading Scheme
Problem 4 In the circuit shown below, the switch has been opened for a very long time prior to t= 0 and closes at t = 0 and remains closed for a long time. Please find: a) i (0), vc(ot), b) the steady-state voltage across the capacitor in terms of Us, Rı, and R2 c) the steady state current through the inductor in terms of Us, Ry, and R2 d) Write the differential equation for it) in terms of Vs,...