Download 4 Unsolved Questions on Organic Chemistry 1 | CHEM 3311 and more Exams Organic Chemistry in PDF only on Docsity! CHEMISTRY 3311, Fall 2003 Professor Walba Second Hour Exam, October 23 scores: 1) 24 2) 25 3) 25 4) 26 100 PLEASE read the questions carefully! CU Honor Code Pledge: On my honor, as a University of Colorado at Boulder Student, I have neither given nor received unauthorized assistance. Name (printed): _________________________________ Signature: ______________________________________ Recitation TA Name: _____________________________ Recitation day and time: ___________________________ This is a closed-book exam. The use of notes, models, calculators, and other paraphernalia will not be allowed during the exam. Please put all your answers on the test. Use the backs of the pages for scratch. H He Li Be B C N O F Na Mg Al Si P S Ne Cl Ar Br I 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 35 53 1A 2A 3A 4A 5A 6A 7A 8A Partial Periodic Table Name: -2- 1) (24 pts) a) A Fischer projection of a sugar with four carbons (1a) is given below. Complete the wedges and dashes structure (1b) for the same compound. CHO CH2OH OHH HHO b) Indicate the configuration (R or S) of each chirality center for your structure 1b. 1a 1b HO O H OH OH R S Name: -5- 3) (25 pts) Propose reagents for accomplishing the following transformations. NOTE: more than one step may be required! Try to make your synthesis efficient (i.e. the desired product should be the major product). You must use the starting material given; you may use any other reagents you need. a) b) c) d) e) OCH3 Br rac OH OH rac Br rac Br Br H2, Pd/C Br2, CH3OH HBr 1) cat H2SO4, ∆ 2) a) BH3 • THF b) H2O2, NaOH 1) CH3O , CH3OH 2) HBr, Peroxides Name: -6- 4) (26 pts) Propose an arrow-pushing mechanism for each of the following transformations. Carefully show the structure of all of the intermediates in your mechanism. a) b) c) Give the NAME of the mechanism from part 4b: Br2, H2O OH Br Br CH3O CH3OH Na Br Br Br H O H O Br H HOH Br BrH H CH3O E2 Name: -7- 4) –continued- d) e) Give the NAME of the mechanism from part 4d: Br CH3OH E1 Br = H
