CHEM 336 Winter, 1997 Final Exam: Organic Chemistry, Exams of Organic Chemistry

Download CHEM 336 Winter, 1997 Final Exam: Organic Chemistry and more Exams Organic Chemistry in PDF only on Docsity! CHEM 336 Winter, 1997 FINAL EXAM Name . Prof. Sasaki 175 points TOTAL Good Luck! Note: Only answers in the box will be graded. ________________________________________________________________________ 1. (35) (a) Write a reasonable mechanism for the conversion of diketone 1 into the important perfumery ingredient cis-jasmone (2). Use curved arrows to indicate the movements of electrons. H3C O O CH2CH3 NaOH EtOH / H2O heat O CH3 CH2CH3 1 2 (b) There is another possible cyclopentanone that could be formed from 1. What is its structure? Write an arrow formalism mechanism for its formation. CHEM 336 page 2 Name . 2. (35) (a) This problem introduces another alcohol protecting group, methoxymethyl (MOM), particularly popular in the month of May. The MOM protecting group is stable to base, but can be cleaved upon treatment with mild acid. Provide a reasonable mechanism for the introduction and cleavage of the MOM protecting group. Use curved arrows to indicate the movement of electrons. R-OH 1) NaH 2) CH3OCH2Cl R-O-CH2OCH3 H+ H2O R-OH MOM introduction cleavage (b) Draw structures for the following compounds. (i) an enamine (ii) a hemiketal (iii) 18-crown-6 (iv)bromoform