chemistry 242 exam 3 2008

chemistry 242 exam 3 2008 - CHEMISTRY 242 THIRD EXAMINATION...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Wednesday, November 19, 2008 Professor William P. Dailey KEY 1. (8 Points) The acidity of pentane-2,4-dione is different than that of dimethyl malonate. Explain which hydrogen(s) are the most acidic in each compound, provide an estimate for the pKa of each compound, state which compound is most acidic, and EXPLAIN why there is a difference in acidity between the two. CH 3 O O O CH 3 H 3 C O O H 3 C O pKa=9 pKa=13 Protons alpha to a ketone functional group are more acidic than those next to an ester functional group because the carbonyl carbon atom has great positive charge compare to that of the ester. This is because the ester oxygen can help to stabilize the positive charge. When these effects are added, the diketone is a much more acidic than the diester. O O O O O O O O 2. (6 Points) Explain why ethyl isopropyl ketone can exchange three hydrogen atoms under basic conditions, while the bicyclic ketone will only exchange two hydrogen atoms under identical conditions. O
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 6

chemistry 242 exam 3 2008 - CHEMISTRY 242 THIRD EXAMINATION...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online