Write a mechanism for the bromination of trans- cinnamic acid that proceeds through a bromonium ion intermediate that clearly shows the stereochemical outcome of the reaction. Draw perspective drawings of the products produced and indicate the configuration (R or S) at each stereocenter.

The following reaction involves two sequential Heck reactions. Draw structural formu- las for each organopalladium intermediate formed in the sequence and show how the final product is formed. Note from the molecular formula given under each structural formula that this conversion corresponds to a loss of H and I from the starting material. Acetonitrile, CH,CN, is the solvent. 1% mol Pd(OAc), 4% mol Ph,P CH,CN C4H171 C4H16

Draw the most stable resonance form for the intermediate in the following electrophilic substitution reaction. CH3 CH3 H3PO4 HO, + H3C CH3 HO HO First stage in synthesis of the epoxy and polycarbonate ingredient bisphenol-A You do not have to consider stereochemistry. Include all valence lone pairs in your answer. In cases where there is more than one answer, just draw one.

The reaction between isocyanide 1 and ketone 2 occurs only after a base (t-BuOK) is added to a solution of the reactants in ethanol and CH2Cl2. The final product is nitrile 4, which is believed to arise from ethanolysis of intermediate 3 under the reaction conditions. Draw a plausible reaction mechanism to describe the formation of 4 from 1 and 2. Draw all intermediates and show all electron-pushing. You are not expected to know if your proposed mechanism is the actual mechanism supported by experimental evidence, but it must be reasonable, and the electron pushing should be correct. Hint: start by deprotonating 1 and forming the first bond, then label and map the atoms onto the intermediate. Ts Ts = ONS=O N=C= t-BuO K H -- EtOH, CH2Cl2 2 3 NEC

Predict the product(s) of the following reactions, including stereochemistry when necessary and identify the mechanism of each substitution reaction (SN1 vs SN2). Draw the reaction mechanism (reaction arrows) for any one of the reactions to show how the product is formed.

Given the following compounds and boiling points: Determine the IMFs Order the compounds from weakest to strongest IMFs, and Pentane (C5H12)                                     36°C Methane (CH4)                                     -164°C Sodium n-butoxide (C4H9NaO)      +260°C Hydrogen dioxide (H2O)                   100°C

Propose a mechanism for the following reaction. Draw out the each step of the reaction including ALL intermediates. CI A CO₂ Et + inte NaO6t EtOH CTS Eta₂c,