Ch. 15 - Analytical Techniques: IR, NMR, Mass SpectWorksheetSee all chapters
All Chapters
Ch. 1 - A Review of General Chemistry
Ch. 2 - Molecular Representations
Ch. 3 - Acids and Bases
Ch. 4 - Alkanes and Cycloalkanes
Ch. 5 - Chirality
Ch. 6 - Thermodynamics and Kinetics
Ch. 7 - Substitution Reactions
Ch. 8 - Elimination Reactions
Ch. 9 - Alkenes and Alkynes
Ch. 10 - Addition Reactions
Ch. 11 - Radical Reactions
Ch. 12 - Alcohols, Ethers, Epoxides and Thiols
Ch. 13 - Alcohols and Carbonyl Compounds
Ch. 14 - Synthetic Techniques
Ch. 15 - Analytical Techniques: IR, NMR, Mass Spect
Ch. 16 - Conjugated Systems
Ch. 17 - Aromaticity
Ch. 18 - Reactions of Aromatics: EAS and Beyond
Ch. 19 - Aldehydes and Ketones: Nucleophilic Addition
Ch. 20 - Carboxylic Acid Derivatives: NAS
Ch. 21 - Enolate Chemistry: Reactions at the Alpha-Carbon
Ch. 22 - Condensation Chemistry
Ch. 23 - Amines
Ch. 24 - Carbohydrates
Ch. 25 - Phenols
Ch. 26 - Amino Acids, Peptides, and Proteins

Concept #1: 1H NMR Chemical Shifts

Example #1: Ranking Shielded Protons

Practice: Which of the labeled protons absorbs energy most upfield in the 1H NMR? 

Practice: Which of the labeled hydrogens will be most de-shielded? 

Practice: Which compound possesses a hydrogen with the highest chemical shift for its 1H NMR signal? 

Additional Problems
Which of the following is a correct prediction of the chemical shifts for the signals in the 1H NMR spectrum for the following compound? a) I=3.9 ppm, II=2.2 ppm, III=2.4 ppm b) I=3.7 ppm, II=2.7 ppm, III=1.9 ppm c) I=3.7 ppm, II=2.2 ppm, III=1.9 ppm d) I=3.9 ppm, II=2.7 ppm, III=1.9 ppm e) none of these
Which of the labeled peaks would allow the distinction of an aldehyde from a ketone based on this spectrum? a. 1 b. 2 c. 3 d. 4 e. 5
Which of the labeled protons would absorb furthest downfield in an NMR spectrum?
Order the following protons from lowest to highest chemical shift value. a Ha < Hc < Hb < Hd b Ha < Hc < Hd < Hb  c Hc < Ha < Hd < Hb  d Hc < Ha < Hb < Hd  e Hc < Hd < Ha < Hb
Which of the indicated protons in the following compound would appear most downfield in the 1H NMR spectrum? a. I b. II  c. III d. IV  e. V
Which of the following compounds will display a singlet, a triplet and a quartet in its 1H NMR spectrum? a.  2-chloro-4-methylpentane  b. 3-chloro-2-methylpentane  c. 3-chloropentane  d. 1-chloro-2,2-dimethylbutane e. 3-chloro-3-methylpentane
Consider all of the spectroscopic information given below. The molecular formula is C10H12O. Provide a structural formula which is consistent with all of the given information; give the index of hydrogen (H2) deficiency.
Which hydrogen of 1-chloropent-2-ene shows the largest chemical (downfield) shift in its NMR spectrum? a. the H on C-1 b. the H on either C-2 or C-3 c. the H on C-4 d. the H on C-5
A computer program capable of predicting chemical shifts was utilized for the structure below. Evaluate the results by answering the following questions. a. Which protons were miscalculated?  b. Are you predicting that the experimental chemical shift will be in higher or lower field? c. Why?
What is the most likely chemical shift for the aldehyde C-H in  1H NMR? a) 1.0 b) 1.5 c) 4.0 d) 5.5 e) 10  
What is the most likely chemical shift for the CH 3OCH3 in 1H NMR? a) 1.0 b) 1.5 c) 4.0 d) 5.5 e) 10
In the  1H NMR spectrum of 1-fluorobutane, the most deshielded hydrogrens are those bound to
Circle the molecule that corresponds to the NMR spectrum shown below.
Consider the following compound whose protons are labeled as a, b, c, d and e. Its   1H NMR spectrum is also shown below. Circle the proton that shows a quintet at δ3.55 ppm.  
Which is the correct order, from lowest to highest field for the chemical shifts, of the numbered sets of protons in the 1H NMR spectrum of this compound? A) 3 < 2 < 1 B) 2 < 1 < 3 C) 1 < 2 < 3 D) 2 < 3 < 1