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235 – Organic II REACTIONS OF CONJUGATED DIENES Just like alkenes, conjugated dienes undergo the ionic addition of HBr; however, the addition to conjugated dienes proceeds by two pathways. Final Exam Review PROBLEMS 85 SPECTROSCOPY Chapter 5: INTEGRATED below. under the compound. if C H O are given 13 the using the method shown First Hour for a compound 9 10 along shown on the right arrow; you may add additional "numbers" C NMR with in Exam the IR spectrum structure clearly 13 thespectra, 1write for each of the compounds H NMR numbers on the 1 H and C NMR and and9. a synthesis each compound Suggest Mass, IR,and this Chemis The ts required next to the for˚C). obtained from spectrum, the try which a structure point 22-24 235,you show reagents/reactan ) suggest (melting Data for the mass Clearly Fall information 21. provided,solid per box total)2014 Sample 11.92. the O,indicate clearly a neutral, low-melting provided, points 27 isinformation the spectral necessary. (4 -points Second Hour on structure; 25 Compound spacesC, 80.56; H, 7.51; Based short Analysis: answer Also, in the for the correct Exam below.Elemental below. question are given spectrum, 5 points space data,provided s are 3 points for each Section I – Nomencl O (5 points each; others spectral source. ature & M/C as marked. 119 In the space provided, Mass Spectrum (4 points each) below, write an acceptab give the correct 91 le IUPAC IUPAC name ______________ name for the for the compound1. molecule shown ______________ shown on the CH2 CH right. on the right: 3 _______ 2. In the 2. ______________ a Claisen condensation space below, _____________ write an acceptab 134 le IUPAC ______________ name for the 65 CH3 molecule shown CH ______________ 3 on the right: 1. ______________ __________________ 3. In the ______________ space below, __________________ O 200 ______ write an acceptab 180 190_________ 150 160 170 _____ le IUPAC 120 130 140 O 90 100 110 ______________ name for the 70 80 60 50 40 30 molecule shown ______________ Brm/e -1 OH on the right: cm ______________ 700 H Wave Number, 800 NO 900 ______________ 1000 Infrared Spectrum 2 1. 1300 1200 1100 4. Which 1500 ______ 2000 2500 of the followin 4000 3000 a. in the proton-c g is true regarding 2. an aldol condensation 2. _________ the 13C NMR oupled 13C b. aldehyde NMR, aldehyde __________________ of carbonyl s and CH3 c. compounds: carbons will the carbonyl ketones will typically __________________ O appear as doublets absorbance absorb at values d. answers _____ from a ketone a) and c), only, e. will always ≈ 200 ppm answers a), appear as a b) and c) are are correct. O singlet all correct. 5. Chlorine exists O chlorine atom as two major isotopes; 35 O will Cl, 75%, and 37 a. two molecula have: Cl, 25%. In 15 r ions, in the the mass spectrum 14 b. four 13 OCH2CH3 12 ratio 3:1 11 molecula 3. _________ CH3 10 9 , a compoun 8 c. 7 + two molecula r ions, in the ratio d with O 5 microns 4 one6 _________ 3 Wavelength,_________ O __________________ d. two molecula r ions, in the ratio 1:3:3:1 2:1 _____ e. three molecular ions, in the ratio 1: 1 3 H NMR CH3 1 r ions, in the Cl ratio 1:2:1 6. The base 1. peak in the 3 4. Which of mass spectrum the compounds synthesis of toluene, 2. shown below an acetoacetic ester quartet, 22.0 a. would be ppm; quartet, CH3 , is most b. likely to be 50.0 ppm; doublet, most consistent with the following 13 singlet, 142.8 due to: ppm; singlet, CH3 c. 129.1 ppm C spectral 167.0 Chemistry All multiple 235 – Sample Br choice and In the space Absorbance Intensity 1. d. 7. CH2 H3 C 2 2 O O CH 3 CH2 OH 5. b. O c. H OCH3 O H3 CO 2 1 ppm, δ 0 CH3 ppm; doublet, d. O OCH + HBr 2 data: 129.7 ppm; O e. CH3 O 4 O 3 3 1. 4 Cl intermedia 5 te formed in an acyl transfer reaction, 2. the strongest base the best anionic Structure: leaving group the most stable will be: anion the group with the the phenoxy group highest pKa the group having the weakest conjugate acid 6. Which of the following CN is correct regarding the spectroscop y of acyl compounds a. the frequency ? of the carbonyl Br 1. absorbance of acyl carbonyl b. in the mass towards nucleophilic addition acyl compounds in the IR generally parallels spectrum, the 2. reactivity c. most common the 1H NMR absorbance of the fragmentation of acyl compounds of d. a and c, only, are correct carboxylic acid protons is is expulsion of very highly deshielded e. statements carbon monoxide a, b and c are correct statements 7 CH3 In the tetrahedral ; singlet, 127.5 ppm a. e. The major bands in the a. infrared spectrum 3150 cm -1; 2200 cm -1; of benzyl alcohol b. 3450 1610 cm -1; cm -1; 3100 will be: 1450 cm -1 cm -1; 2930 c. 2930 cm -1; cm -1; 1760 2450 cm -1; cm -1 d. 3450 1610 cm -1 cm -1; 3100 cm -1; 2930 e. 3450 cm -1; cm -1; 1600 3100 cm -1; cm -1 2200 cm -1; 1600 cm -1 8. Which of the followin 13 C Spectral Data: a. in the 1H NMR, g is not true regarding the phenyl the spectra b. the 13 196.5 ppm group will of 4-methyl C NMR will singlet, appear as two benzonitrile: c. have two singlets 142.1 ppm the IR spectrum singlet, doublets and two will d. in the 1 134.4 ppm singlet, in the H NMR, the display by a significa doublets “aromati ppm e. 129.1 nt absorptio CH doublet, in the mass n at aboutppm c region” spectrum, 3 group will absorb at doublet, 128.5 2200 cm -1 the base peak approxim ately will most likelyquartet, 2.2ppm 22.8 ppm be at m/z 20.9=ppm quartet, 91 1,2 addition 3 1 6 a. b. c. d. e. an intramolecular aldol condensation O alkylation of an enamine Br 1,4 addition Reproduction or distribution of any of the content, or any of the images in this presentation is strictly prohibited without the expressed written consent of the copyright holder. © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 CH2 H REACTIONS OF CONJUGATED DIENES REACTIONS OF CONJUGATED DIENES + HBr In the 1,4-addition, protonation on the terminal carbon generates the allylic carbocation, with cationic character on both carbons #1 and #3. In the 1,4-addition, protonation on the terminal carbon generates the allylic carbocation, with CH2 cationic character on both carbons #1 and #3. H allylic carbocation CH2 δ δ H Br CH2 + HBr - H Br The addition of Br– to carbon #1 of the diene gives the 1,4-addition product. CH2 H allylic carbocation δ © ChemistryOnline, 2009-2014 δ © ChemistryOnline, 2009-2014 Br CH2 - Br H 1,2 VS 1,4 ADDITION REACTIONS OF CONJUGATED DIENES For 1,2 and 1,4-additions the following trends are observed: REACTIONS OF CONJUGATED DIENES The two products are also referred to as the kinetic product; and the thermodynamic product. • The 1,2-addition product forms rapidly at low temperatures. Kinetic product (faster). • The 1,4-addition product is predominant at higher temperatures. • Even at low temperatures, 1,4-addition products will predominate if given enough time. • The addition of HBr to butadiene is reversible and isolated 1,2-addition product will convert to the 1,4-product at higher temperatures or at longer times. © ChemistryOnline, 2009-2014 Br 1,2 addition 3 + HBr 1 2 4 Thermodynamic product (slower, but more stable). Br 1,4 addition © ChemistryOnline, 2009-2014 HBr 1,2-addition IN-CLASS PROBLEM HBr 1,4-addition REACTIONS OF CONJUGATED DIENES Predict the major products for the following reactions: The Diels-Alder reaction; 4 + 2 Cycloadditions. HBr 1,2-addition heat + ...and a dienophile a diene... HBr 1,4-addition heat + HBr 1,2-addition O HBr 1,4-addition + O This is called an electrocyclic reaction. heat CH3 C © ChemistryOnline, 2009-2014 CH3 © ChemistryOnline, 2009-2014 HBr 1,2-addition HBr 1,4-addition THE (4N + 2) RULE REACTIONS OF CONJUGATED DIENES Cl2/CCl4 The Diels-Alder reaction; 4 + 2 Cycloadditions. The resonance description of benzene will explain the geometry of the molecule and the isomer distribution of benzene derivatives, but does not explain the unusual stability of benzene and its derivatives. heat + The stability of benzene is suggested to arise from the fact that the conjugated π system is planar and contains 4n + 2 electrons (with n = 1), and it is suggested that all compounds having planar, conjugated π systems containing 4n + 2 electrons will share this stability. This property, described originally by Hückel, is referred to as aromaticity. heat + O O + CH3 heat C CH3 © ChemistryOnline, 2009-2014 THE (4N + 2) RULE © ChemistryOnline, 2009-2014 THE (4N + 2) RULE Consider the following molecules: Consider the following molecules: 4 π electrons not aromatic 6 π electrons aromatic © ChemistryOnline, 2009-2014 6 π electrons aromatic 8 π electrons not aromatic 6 π electrons aromatic © ChemistryOnline, 2009-2014 REACTIONS OF AROMATIC SIDE-CHAINS CH3 REACTIONS OF AROMATIC SIDE-CHAINS Oxidation with neutral MnO4- MnO4 /H2 O, heat CH3 COOH - MnO4 /H2 O, heat CH2 CH2 CH3 - MnO4 /H2 O, heat CH3 COOH COOH COOH - MnO4 /H2 O, heat - MnO4 /H2 O, heat © ChemistryOnline, 2009-2014 REACTIONS OF AROMATIC SIDE-CHAINS REACTIONS OF AROMATIC SIDE-CHAINS Allylic bromination with NBS CH3 © ChemistryOnline, 2009-2014 Dissolving Metal Reduction of Benzene Derivatives The Birch Reduction CH2 Br NBS/CCl4 "radical initiator" Li/NH3 Br CH2 CH2 CH3 CHCH2 CH3 NBS/CCl4 "radical initiator" CH3 Br OCH3 NBS/CCl4 "radical initiator" CH3 Li/NH3 OCH3 Li/NH3 © ChemistryOnline, 2009-2014 REACTIONS OF AROMATIC SIDE-CHAINS ELECTROPHILIC AROMATIC SUBSTITUTION Predict the products of the following reactions Br Predict the products of the following reactions. © ChemistryOnline, 2009-2014 C X+ NBS/CCl4 "radical initiator" R RC≣O+ Br Acylation Halogenation COOH - MnO4 /H2 O O X Nitration NO2+ HOOC NO2 Alkylation R+ R Sulfonation HSO3+ SO3H Li/NH3 © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 HALOGENATION REACTIONS NITRATION REACTIONS Br Br Fe Br H2SO4 + HNO3 Br NO2+ + H2O Br Br Br2/FeBr3 NO 2 Br HNO3 H Br2/AlBr3 NO 2 H H2SO4 Cl Cl2/FeCl3 Cl H Cl2/AlCl3 © ChemistryOnline, 2009-2014 SULFONATION REACTIONS © ChemistryOnline, 2009-2014 FRIEDEL-CRAFTS ALKYLATION Br H2SO4 + SO3 HSO3+ + HSO4- Br Fe Br CH3 Br SO3H SO3 CH3 SO3H CH3Br H FeBr3 H2SO4 © ChemistryOnline, 2009-2014 FRIEDEL-CRAFTS ALKYLATION © ChemistryOnline, 2009-2014 FRIEDEL-CRAFTS ACYLATION Br Br Fe Br Br CH3 Br Br COOH COOR OO C Br CHCH 3 3 O O 2. Reaction does not occur on rings containing strong electron withdrawing substituents. O CN Fe Br 1. Reaction limited to alkyl halides; aryl or vinyl halides do not react. NO 2 CH3 H SO3H CHO NR 3+ O C CH3 C Br CH3 H C CH3 FeBr3 C R 3. Multiple substitutions often occur. 4. Carbocation rearrangements can occur, particularly with 1˚ alkyl halides. © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 FRIEDEL-CRAFTS ACYLATION the products of the following reactions. I1.(con't) N-CLASS Predict PROBLEM Br Br OO Fe Cl2 C Br FeCl3 CHCH 3 3 Br Cl 1. Multiple substitutions do not occur. SO3 /H2 SO4 2. Carbocation rearrangements do not occur. O 3. Reaction does not occur on rings containing strong electron withdrawing substituents. O 4. Acid anhydrides can also be used. H3 C O O O O AlCl3 CH3 © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM: REACTIVITY OF SUBSTITUTED BENZENES NH2 Strongly Activating CH3 OH N CH3 ortho & para directing C CH3 O SO3 H Br2 /FeBr3 Cl Br I CHO SO3 H NO2 Strongly Deactivating Cl2 /FeCl3 H OCH3 H F © ChemistryOnline, 2009-2014 COOR COOH CN NR3 NO2 COR I2 /CuCl2 meta directing + © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM IN-CLASS PROBLEM Cl 3 CH ClCH3 SOCl 3 /H 2 SO43 2 /FeCl CH33H SO excess Br HNO 3 /H23SO4 2 /FeBr C Cl O HO 1. BH 4 + NO2 O 1. BH 4 - H 2. H 3 O CH3 1. BH 4 O O © ChemistryOnline, 2009-2014 OH H + CH(CH3 )2 NO2 I H - 2. H 3 O CH SO3 H 3 Br O2 N AlCl I2 /CuCl 3 2 O Reactions that yield alcohols: + ortho isomer 2 isomer +NO ortho HO3 SCl CH(CH NO 3 )2 2 © ChemistryOnline, 2009-2014 H HO H + 2. H 3 O CH3 © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM IN-CLASS PROBLEM Reactions that yield alcohols: Reactions that yield alcohols: O H H 1. LiAlH4 , ether CH3 O O HO H + CH3 Br + 2. H 3 O Br O OH 1. LiAlH4 , ether + 2. H 3 O O 1. Mg/ether + 2. H 3 O 1. Mg/ether + 2. H 3 O + H O OH OH 1. LiAlH4 , ether + 2. H 3 O O CH3 H H © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM Br 1. Mg/ether + 2. H 3 O H © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM Suggest two syntheses for the molecule shown below, using a Grignard Reaction. Reactions that yield alcohols: O 1. LiAlH 4 , ether OH + OH + 2. H 3 O from a carboxylic acid OH O 1. LiAlH 4 , ether OH + 2. H 3 O OCH3 from an ester O H H 1. Mg, ether + 2. H 3 O OCH3 Br + Br OH from an ester © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM Utilizing any one of the starting materials shown on the right, suggest a synthesis of the following compound: © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM O O Br CH2 OH O CH3 O C H CHO O OH H O Br CH2 OH O CH3 O C H CHO O OH H Br O O Utilizing any one of the starting materials shown on the right, suggest a synthesis of the following compound: O CH2 OH H © ChemistryOnline, 2009-2014 OH © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM IN-CLASS PROBLEM Predict the products for the following substitution reactions. Predict the products for the following reactions of epoxides. 1. Predict the products of the following substitution reactions. CH2 Br CH3 O MgBr, ether 1. CH2 --OCH3 O OH + 2. H /H2 O O CH2 Br CH2 CH3 CH2 CH3 O + H /H2 O O OH OH O H C C CH2 OTos H H O C C CH2 O - 1. CH 3 CH2 O O + 2. H /H2 O OH © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM IN-CLASS PROBLEM Beginning with benzyl bromide, suggest a synthesis of the compound shown below: Beginning with benzyl bromide, suggest a synthesis of the compound shown below: O CH2 Br CH3 CH2 Br CH3 O CH3 © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 O O O H OC H2C H3 CH2 CH3 H2C H3 O O O CH3 OCH2 CH3 OC CH3 - + CH3 CH2 O O H O O CH2 CH3 O O O H H3 O CH3 CH2 O OCH2 CH3 CH3 CH2 H © ChemistryOnline, 2009-2014 CH3 O CH3 O CH 2 CH 3 O O H O CH3CH2O- H2C OC OH CH3 O CH CH3 - HO O CH2 CH3 O H O O - O CH3 CH2 O H - /EtO EtO O 2 CH3 H H O O HOH CH3 CH2 O EtO CH3 - The base-catalyzed condensation of two moles of an O ester is called the Claisen Condensation. O H CH 2 CH 3 OH CH3 CH2 CH3 O O CH 3 The base-catalyzed condensation of two aldehydes or ketones to form a β-hydroxy aldehyde or ketone is known as the Aldol Condensation. 2 O CH3 + CH3 CH2 O CARBONYL CONDENSATION REACTIONS CARBONYL CONDENSATION REACTIONS O O CH 2 CH 3 2 CH3 CH2 CH3 CH2 CH3 O © ChemistryOnline, 2009-2014 CARBONYL CONDENSATION REACTIONS REACTIONS OF α,β-UNSATURATED CARBONYLS An intramolecular Claisen is called the Dieckman O O O Condensation. O OOCH 3 OO O OCH 3 OCH CH3 3 HC 2H C O OCH3O O O 3H H OCH3 OCH 3 H OO CHCH O3 O O 3 - HO tE/ -O tE O O OCH3 δ Nuc Nuc O δ δ Nuc Nuc Nuc Nuc O δ O δ H + H + O O O O © ChemistryOnline, 2009-2014 O O H H O H OH 2 C O 3 HC 3 HC O O O NC CN (CH3))2CuLi CuLi (CH (CH332)2 CuLi O O O O O NC NC NC NC CH3 O OCH3 O NC O NC O CH3 CH3 OCH3 O CH3 O O O OCH3 © ChemistryOnline, 2009-2014 OCH3 CH3 CH3 © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM 3-Buten-2-one is subjected to the four steps shown below; what will beOthe major product of reaction CHthis 3 sequence? O CH3 - O CH3 O O2 N CH3 O N O OCH3 CH3 O O O CH3 O CH3 NC CN O Michael addition of enamines and nitroalkanes. O O O O CH3 O OCH CH CH333 N NN H OHH O OCH3 CH3 O O CH CH3 OO 3 O O O N OCH3 O CH3 REACTIONS OF α,β-UNSATURATED CARBONYLS CH3 O O OCH3 O O O CH3 CH CH33 NC O CHCH NH 3 3NH CH CH33 NH222 O O O Enolate anions also undergo the Michael Reaction: 3 (CH CH2))2AlCN AlCN OCH3 CH3(CH O 333CH (CH CH222)2 AlCN CH3 O REACTIONS OF α,β-UNSATURATED CARBONYLS The Michael additions of α,β-unsaturated ketones and aldehydes that we covered include: OCH O CH3 O O O O © ChemistryOnline, 2009-2014 OCH3 OCH 3 REACTIONS OF α,β-UNSATURATED CARBONYLS O δ O 3 HC 2H C 3 HC OH 2 C O OtE OCH O O 3 O 3 HC H O OCH 3 OCH α Conjugated ketones and aldehydes can undergo an analogous reaction in which a nucleophile adds to the terminal carbon of the double bond. OCH3 OCH 3 2 HC O O HC 3 O OOCH 3 β O O CH3 O C2H CO HO O O O OCH3 + CH3 O OCH3 OCH 3 - O+ +CHCH 3 O3 O- 3 The Michael Reaction of α,β-unsaturated ketones and aldehydes. O O OCH3 CH3 + 2. H /H2 O; heat 3. OH /H2 O + 4. H /H2 O CH3 O CH3 + 2. H /H2 O © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM IN-CLASS PROBLEM Beginning with cyclohexanone, suggest a simple synthesis for the following compound: O O Beginning with cyclohexanone, suggest a simple synthesis for the following compound: OH O O 1. HO O - 1. LDA 2. CH 3 CH2 Br + 2. H /H2 O H © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM IN-CLASS PROBLEM Beginning with cyclohexanone, suggest a simple synthesis for the following compound: Beginning with cyclohexanone, suggest a simple synthesis for the following compound: H O O O H CH3 NH2 /BH3 CN 1. Br 2 /CH3 COOH 2. Pyridine 3. (CH 3 CH2 )2 AlCN N - CN © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 IN-CLASS PROBLEM IN-CLASS PROBLEM Predict the products for the following reactions: O Predict the products for the following reactions: H H2 N C Cl + H O N 1. NaBH 3 CN N + + SO2Cl NH2 CH3 O 1. 1. CH2 N NH + O Br Br + - O CH2 Br SO2 N H - N 2. H 3 O O CH3 N K CH3 NH2 2. HO /H2 O © ChemistryOnline, 2009-2014 Cl 1. NaN 3 2. heat, H 2 O NH2 © ChemistryOnline, 2009-2014 FORMATION OF DIAZONIUM SALTS IN-CLASS PROBLEM Predict the products for the following reactions: O NaOH, Br 2 , H 2 O N NH2 NH2 NH2 O O O HNO2 H2 SO4 CH3 OCH 3 N CH3 NH2 OCH3 N H NH2 ...a diazonium salt... 1. CH 3 NH2 (excess) 2. Ag 2 O, H 2 O, heat © ChemistryOnline, 2009-2014 REACTIONS OF DIAZONIUM SALTS © ChemistryOnline, 2009-2014 REACTIONS OF DIAZONIUM SALTS H3 PO2 , H 2 O KCN, CuCN HCl, CuCl N2 + H /H2 O + N2 + OH HBr, CuBr CH3 N KI CH3 © ChemistryOnline, 2009-2014 INTEGRATED SPECTROSCOPY: COMPOUND #1 MW = 134.18 INTEGRATED SPECTROSCOPY: COMPOUND #1 C9H10O 119 134 65 30 40 50 60 70 80 90 Wave Number, cm -1 MW = 134.18 4000 3000 2500 2000 1500 1300 1200 1100 1000 900 800 700 Absorbance 91 Intensity C9H10O © ChemistryOnline, 2009-2014 . 100 110 120 130 140 150 160 170 180 190 200 m/e . 3 4 5 6 7 8 9 10 Wavelength, microns 11 12 13 14 15 3400 cm-1 : 3100 cm-1 : 2900 cm-1 : 2750 cm-1 : 1710 cm-1 : 1610 cm-1 : © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 INTEGRATED SPECTROSCOPY: COMPOUND #1 MW = 134.18 C5H9O2Br MW = 181.03 107-110 Intensity C9H10O INTEGRATED SPECTROSCOPY: COMPOUND #2 135-137 30 40 50 60 70 80 90 100 110 120 130 140 180-182 150 160 170 180 190 200 m/e 3 C Spectral Data: 13 2 singlet, 196.5 ppm singlet, 142.1 ppm singlet, 134.4 ppm doublet, 129.1 ppm doublet, 128.5 ppm quartet, 22.8 ppm quartet, 20.9 ppm 2 7 6 5 3 4 3 2 1 ppm, δ 0 © ChemistryOnline, 2009-2014 © ChemistryOnline, 2009-2014 INTEGRATED SPECTROSCOPY: COMPOUND #2 INTEGRATED SPECTROSCOPY: COMPOUND #2 Wave Number, cm -1 C5H9O2Br MW = 181.03 2000 1500 1300 1200 1100 1000 900 800 C5H9O2Br MW = 181.03 700 Absorbance 4000 3000 2500 3 4 5 6 7 8 9 10 Wavelength, microns 11 12 13 14 15 C Spectral Data: 13 3400 cm-1 : 3100 cm-1 : 2900 cm-1 : 2200 cm-1 : 1710 cm-1 : 1610 cm-1 : 3 singlet, 172.0 ppm; triplet, 59.5 ppm; doublet, 57.7 ppm; quartet, 20.4 ppm; quartet, 13.6 ppm 2 1 7 © ChemistryOnline, 2009-2014 3 6 5 4 3 2 1 ppm, δ 0 © ChemistryOnline, 2009-2014 .