Reaction 2: (d) Consider the following reaction that proceeds via a concerted mechanism. Add arrows to indicate the movement of electrons. OCH3 OCH3 (e) The electrophile in the reaction in part (d) is ethylene (H2CCH2). Circle the orbital of the electrophile that must overlap with the nucleophile orbital in this reaction. (f) nonbonding lone pair OC-C OC-0 OC-H TC-C nonbonding p σ*C-C σ*C-0 σ*C-H π*C-C In going from reactants to products in the reaction in part (d), does entropy increase, decrease, or stay about the same?

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Consider the SN2 reaction of butyl bromide with OH- ion. CH3CH2CH2CH2B + OH- → CH3CH2CH2CH2OH + Br Assuming no other changes, what effect on the rate would result from simultaneously doubling the concentrations of both butyl bromide and the OH- ion? Draw the curved arrow mechanism for the SN1 reaction of methanol with tert-butyl iodide. Next, draw an Energy vs. Reaction Coordinate diagram for this reaction, labeling all transition states as "TS" and intermediates as appropriate for those drawn in the mechanism above, showing the relative energies on the diagram.

Acyl transfer (nucleophilic substitution at carbonyl) reactions proceed in two stages via a "tetrahedral intermediate." Draw the tetrahedral intermediate as it is first formed in the following reaction. H3C HCI / H2O `NH2 reflux • You do not have to consider stereochemistry. • Include all valence lone pairs in your answer. • Do not include counter-ions, e.g., Na", I, in your answer. • In cases where there is more than one answer, just draw one. opy aste Previous Next

Draw curved arrows to show the movement of electrons in this step of the mechanism.

b) Explain in detail what characteristics of the alkyl halide influence whether a mechanism will be SN1 or SN2. c) Explain in detail what characteristics of a nucleophile influence whether a reaction will be SN1 or SN2.

(b) Consider the reaction of 1-bromobutane with a large excess of ammonia (NH3). Draw the reactants, the transition state, andthe products. Note that the initial product is the salt of an amine (RNH3+ Br - ), which is deprotonated by the excess ammonia to give the amine.

10) Consider the following alkene hydration reaction. он H2SO, H20 Given that the reaction is endergonic by 10 kcal/mol, complete the following. (a) Draw the intermediate(s) formed in the mechanistic pathway to the major product in the indicated space below. If there are multiple intermediates label them 1, 2, 3, 4, etc. (b) Sketch a reaction-energy profile for this reaction and clearly label staring material, product, intermediate(s), transition state(s), AG" and AG (of the rate determining step) on your plot. Progress of the reaction Draw and Label Intermediate(s) Below: Potential energy

N(CH2CH3)3 + HNO3  --------> a.) rewrite the reaction using bond-line structure of reagents and products of the reaction b.) supply the curved arrows explaining the mechanism of the reaction

.  Use to curved arrow notation, propose a mechanism for the following reaction and state whether it is either SN1, E1, SN2, or E2.  Give the IUPAC names of all organic reactants and products.