Chapter 20, Problem 98CP

iv)Propose a mechanism (curved arrow formalism) for the reaction of the  synthesis of a sulfonamide derivative  from  sulfathiazole

Gamma(y)-amino butyric acid (GABA) is a neurotransmitter (a chemical that is used to send signals from one neuron to another) of the mammalian central nervous system. In order to understand how GABA works, conformationally restricted analogues, such as compound 1, have been made. During a synthesis of compound 1, compound 2 was subjected to allylic bromination using NBS and a radical initiator (AIBN) instead of light (Aust. J. Chem. 1981, 34, 2231-2236). H₂N. CH3 GABA CO₂H CH3 dddd CH3 H₂N Modify the structures given below to draw all eight possible allylic bromides that can be formed when compound 2 undergoes allylic bromination, considering all possible regiochemical and stereochemical outcomes. You can use the single bond tool to add/remove pi bonds. CH3 CO₂H CH3 solddd CH3 CH3 2 CH₂ CO₂Et

1,3,5,7-Cyclooctatetraene, C8H8, is an unusual hydrocarbon in that it reacts with exactly 2 equivalents of potassium to give A, C8H8K2, which can be isolated as a white solid. A exhibits a single proton NMR signal. Draw the structure of A.

A step in a synthesis of PGE1 (prostanglandin E1, alprostadil) is reaction of a trisubstituted cyclohexene with bromine to form a bromolactone. Alprostadil is used as temporary therapy for infants born with congenital heart defects that restrict pulmonary blood flow. It brings about dilation of the ductus arteriosus, which in turn increases blood flow in the lungs and blood oxygenation. Propose a mechanism for formation of This bromolactone, and account for the observed stereochemistry of each substituent on the cyclohexane ring.

Propose mechanisms consistent with the following reactions. (a) (b) (c) (d) (f) (breif Written explantion for each PLEASE) Propose mechanisms consistent with the following reactions. (a) HBr ROOR Br H₂SO4 (b) H₂O OH Br HBr Br (d) (c) CHBr Br NaOH Br Br (e) HCI CH3CH₂OH Br OCH2CH3 Br ED-8 CH2CH3 H- OH H+, H₂O (f) H OH CH3CH2 CH2CH3 CH2CH3 (continued)

3) Venlafaxine is a Wyeth antidepressant that is synthesized on a commercial scale from the starting material shown. Suggest a plausible synthesis using the same starting material. CI MeO MeO H₂N OH

A compound with molecular formula C7H1402 upon hydrolysis produces an alcohol and an acid. It has the following (b) NMR data : 'H-NMR (at 298 K, 600 MHz, CDC13) : 80-92 (d, 6H), 1:52 (т, 2н), 1-69 (m, 1Н), 2-04 (s, ЗH) and 4-09 (t, 2H). 13 C-NMR : 8 21-0, 22:5, 25:1, 37.4, 63·1 and 171-2 ppm DEPT provided two inverted signals. Predict the structure of the alcohol that is obtained through hydrolysis of the mentioned parent compound. Assign appropriate IR values, 'H and 13C-NMR resonances along with a mass spectral pattern for the alcohol.

Mustard gas, Cl¬CH2CH2¬S¬CH2CH2¬Cl, was used as a poisonous chemical agentin World War I. Mustard gas is much more toxic than a typical primary alkyl chloride. Itstoxicity stems from its ability to alkylate amino groups on important metabolic enzymes,rendering the enzymes inactive.(a) Propose a mechanism to explain why mustard gas is an exceptionally potent alkylatingagent

Treatment of (CH3)2CHCH(OH)CH2CH3 with TsOH affords two products(M and N) with molecular formula C6H12. The 1H NMR spectra of M and Nare given below. Propose structures for M and N, and draw a mechanismto explain their formation.