KEY Pre#2-251-06 - ORGANIC CHEMISTRY LECTURE CHY 251(02)...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
ORGANIC CHEMISTRY LECTURE CHY 251(02) Prelim II, 10/24/06 ______ KEY ______ The following section consists of 16 multiple choice questions. Circle the single response that best answers each question. (3 pts/each). 1. Which one of the following functional groups would display the most highly shielded proton in its 1 H NMR spectrum? a) O-CH 3 group d) C-CH 3 group b) CHO group e) CH 2 -Br group c) CH=CH 2 group f) CH 2 -F group 2. There are _ _ _ _ -types of non-equivalent protons and _ _ _ _-types of non-equivalent carbons found in 2,3-dimethylcyclobutene. a) 3; 4 b) 4; 4 c) 3; 5 d) 5; 5 e) 4; 6 f) 6; 6 3. Which one of the following will produce an anisotropic deshielding effect in the 1 H NMR spectrum? a) an alkyl chloride d) a cyclobutane ring b) a nitrile e) a terminal alkyne c) an alkene f) an alcohol 4. The proton NMR spectrum of a compound displays singlets at δ 2.10 and at δ 4.21 with an integration ratio of 3:2 , respectively. Which compound below fits these data? H 3 C O C H 2 H 2 C O CH 3 H 3 C C H 2 H 2 C CH 3 O O H 3 C O H 2 C C H 2 O CH 3 O O O a) c) b) d) H 2 C C H 2 O CH 3 O H 3 C 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
5. The hydrogen indicated by an arrow in the compound shown below would be displayed as a _ _ _ _ _ -line pattern in its proton NMR spectrum. (Consult your J value sheet.) a) 2 b) 4 c) 6 d) 8 e) 10 6. Which one of the following statements explains why the aromatic protons are found downfield in the 1 H NMR window from most other hydrogen-containing functional groups. a) The π -electrons on the aromatic ring shield the protons very effectively. b) The π -electrons give rise to an induced magnetic field that is in the same direction as the applied magnetic field. c)
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 9

KEY Pre#2-251-06 - ORGANIC CHEMISTRY LECTURE CHY 251(02)...

This preview shows document pages 1 - 3. Sign up to view the full document.

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