Exam 13: Structure Determination: Nuclear Magnetic Resonance Spectroscopy

Propose a structure for Compound X,which has M⁺ = 120 and (M + 2) = 122 of approximately equal intensity in its mass spectrum and has the following ¹³C NMR spectral data: Broadband decoupled ¹³C NMR: 32.6,118.8,134.3 δ DEPT-90: 134.3 δ DEPT-135: positive peaks at 134.3 δ;negative peaks at 32.6,118.8 δ

Exhibit 13-10 Answer the question(s) for the compound whose ¹H NMR spectra is shown below. C₄H₈O Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/ -Refer to Exhibit 13-10.Propose a structure for this compound.

​Find all the types of nonequivalent protons in the given compound.

Exhibit 13-1 The following question(s) pertain to the charting of NMR spectra.MATCH a term to each description below. -_____ The exact place on the chart at which a nucleus absorbs is called its _____.

Exhibit 13-1 The following question(s) pertain to the charting of NMR spectra.MATCH a term to each description below. -_____ The calibration standard for ¹H and ¹³C NMR is _____.

Which of the following occurs when a DEPT-135 spectrum is run?

​Identify the different types of protons in 1-chloro-2-butene.What would be the chemical shift observed for each type of proton?

Exhibit 13-9 To answer the following question(s),consider the data and ¹H NMR spectrum below: The mass spectrum of this compound shows a molecular ion at m/z = 113,the IR spectrum has characteristic absorptions at 2270 and 1735 cm−¹,and the ¹³C NMR spectrum has five signals. Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/ -Refer to Exhibit 13-9.Propose a structure for this compound.

Exhibit 13-11 Answer the question(s) for the compound whose ¹H NMR spectra is shown below. C₅H₁₂O Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/ -Refer to Exhibit 13-11.Calculate the degree of unsaturation for this compound.

Exhibit 13-8 Below are three isomeric chlorobutanes and their ¹³C NMR spectral data.MATCH the spectral data to the correct structures by placing the letter of the spectrum in the blank to the left of the corresponding structure. -_____

Exhibit 13-8 Below are three isomeric chlorobutanes and their ¹³C NMR spectral data.MATCH the spectral data to the correct structures by placing the letter of the spectrum in the blank to the left of the corresponding structure. -_____

Exhibit 13-12 Answer the question(s) for the compound whose ¹H NMR spectra is shown below. C₈H₇ClO Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/ -Refer to Exhibit 13-12.Calculate the degree of unsaturation in this compound.

Exhibit 13-9 To answer the following question(s),consider the data and ¹H NMR spectrum below: The mass spectrum of this compound shows a molecular ion at m/z = 113,the IR spectrum has characteristic absorptions at 2270 and 1735 cm−¹,and the ¹³C NMR spectrum has five signals. Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/ -Refer to Exhibit 13-9.How many types of nonequivalent protons are there in this molecule?

Nuclear magnetic resonance spectroscopy provides information about a molecule's:

Treatment of tert-butyl alcohol with hydrogen chloride yields a mixture of tert-butyl chloride (S_N1 product) and 2-methylpropene (E1 product).After chromatographic separation,how would you use ¹H NMR to help you decide which was which?

Propose a structure for Compound Z,which has the following spectroscopic properties: MS: M⁺ = 88 IR: 3380 cm−^{1 1}H NMR: 0.85 δ (6H doublet);1.40 δ (3H multiplet);2.68 δ (1H singlet);3.55 δ (2H triplet) Broadband decoupled ¹³C NMR: 22.7,25.0,41.8,60.5 δ DEPT-90: 25.0 δ DEPT-135: positive peaks at 22.7,25.0 δ;negative peaks at 41.8,60.5 δ

Which of the following provides information about the carbon framework of a molecule?

Exhibit 13-9 To answer the following question(s),consider the data and ¹H NMR spectrum below: The mass spectrum of this compound shows a molecular ion at m/z = 113,the IR spectrum has characteristic absorptions at 2270 and 1735 cm−¹,and the ¹³C NMR spectrum has five signals. Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/ -Refer to Exhibit 13-9.What is the significance of the ¹³C NMR data?

Identify the splitting pattern of the numbered protons.Atoms other than hydrogen and carbon are labeled.

The following is the tree diagram for the protons on a specific carbon. Which of the following signals in a proton NMR could correspond to these protons?