Problem Set 5: Aldehydes and Ketones - Chem 221b, Assignments of Chemistry

Download Problem Set 5: Aldehydes and Ketones - Chem 221b and more Assignments Chemistry in PDF only on Docsity! Chem 221b Problem Set 5 Chapter 18 Aldehydes and Ketones Due: Monday, February 21, 2005 " There are more stories told about Russell Marker than perhaps any other chemist. Although many of these stories are apocryphal, they are so fascinating that most of us cannot bear to stop repeating them. This is the oral history of our profession that we pass to our colleagues and our students. They are the campfire stories that bind our profession together." --Steven M. Weinreb, Russell & Mildred Marker Professor of Natural Products Chemistry, Pennsylvania State University Russell Marker (1902- 1995) There are some practice exercises in the aldehyde and ketone modules in ORGO. 1. Compound A (IR: 1685 cm-1) displays the spectra shown (click on the spectra for larger versions). a) What is the structure of A? b) Assign the resonances in the NMR spectra. c) Assign the peaks (arrows) in the mass spectrum. 2. a) Design a synthesis of ketone 1 from benzene, ethylene, and acetone-d6. [Hexadeuteroacetone is a readily available 1H NMR solvent.] b) Draw a mass spectrum for 1. How does it compare with the mass spectrum in problem 1? c) How would you prepare (±)-2a from 1? d) How would you prepare 2b from 1? 3. In each of the following questions, provide two routes for each chemical transformation. More than one reation in each route may be required. 4. Provide structures for A-I. where mixture are formed, one compound may dominate. For reactions involving an acid catalyst, provide mechanisms.