{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Exam II Fall 2009 - Name Chem 343 K F all 2009 AM class PM...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 6
Background image of page 7
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Name: ' ' ' Chem 343 K _ F all 2009 AM class / PM class (circle One) . _ ‘ Exam II I. For each compound shown below, label each stereocenter as R or S. (10 points) , COzH HO H HO H H . OH - Cogs . D-Arabinaric Acid ’ Ascorbic Acid (Vitamin C) Ritalin . ' Menthol II. When cis-1-chloro-2-methylcyclohexane reacts with sodium methoxide 1n methanol, the reaction proceeds rapidly to give the more stable alkene (1-methylcyclohexene, first reaction shown below). When trans—1-chloro—2-methylcyclohexane reacts under the same conditions, the reaction proceeds slowly to give the less stable alkene (3 -methylcylohexene, second reaction shown below). For each reaction, draw (in the box provided) the most . stable chair conformation of the Starting material. Show the mechanism of the reaction using curved arrows to show the movement of electron pairs. Be sure that your mechanism ' shows the correct chair conformation that leads to the product (not necessarily the most stable chair. (12 points) c1 CH3O _CH3OH CH3 01130 CH3OH ”CH3 Referring to your mechanisms, briefly explain why the second reaction occurs more slowly and why it forms the less stable alkene. (4 points) For each of the following reactions, provide reagents oVer/under the arrow that Would convert the reactant shown to the product shown as the major product. If more than one 111; step is required, number the steps as 1.), 2.), etc. (22 points) 1 ti . . ' Br _‘ IV. Long chain “fatty” alcohols with limited methyl branching, such as 2,1 1-dimethyl-2— dodecanol (shown at right below) have a unique combination of surface activity, solubility and biodegradability that makes them useful as detergent ingredients. Starting from the alkyl dibromide (shown at left below) and typical laboratory reagents, including acetylene, devise a stepv'vise synthesis of 2,1 1-dimethyl—2-dodecanol. (Note: You will need to use the alkyldibromide more than once in your synthesis.) Show a complete reaction, including the necessary reagents, for each step in your synthesis. '(16 points) ' 2,11-dimethyl-2—dodecano’l . V. For each of the following reactions, draw the structure of the major product. If the major product is one specific stereoisomer, be sure to show the correct one If the major product is formed as equal (or approximately equal) amounts of two stereoisomers, clearly indicate which two are formed. (4 points each = 36 points) 0 Ace OTf ——-—-————-————-> V/W CH3C02H e - ——————————,_> ' 2.) H3CBr . e CH3)3CO ( ———————> (GHQSCOHW 7, : 1.)eNH2/NH3 2.) CH3CH2CH2Br V 3.) HZ/Pd(CaCO3) (Lindlar's Catalyst) H3COe H3COH B, ' H3COH H300 H3COH Namei AM class / PM class.(circle one) Question I II. III. IV. Total I ' Points Chemistry 343 Fall 2009 Exam H v ...
View Full Document

{[ snackBarMessage ]}