CHM!2202! ! Department!of!Chemistry!Organic!Chemistry!Lab!II! ! Villanova!University!!!!!Infrared!Absorption!Bands!!!Important!OH,!NH!and!CH!Singl e!Bond!Stretching!Absorptions!!!Important!CC!and!CN!Triple !Bo n d!Stretching!Absorptions!Bond!Type! Family!Frequency!Range,!cm"1!Comments!C!!C!Alkyne! 2260!–!2100! Weak!–!medium!!!C!!N!Nitrile! 2260!–!2220!! Medium!!!Important!CC,!CN!and!CO!Doubl e !Bond!Stretching!Absorptions!Bond!Type! Family!Frequency!Range,!cm"1!Comments!O!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!RHC"""""H!Aldehyde! 1740!–!1685! Strong!O!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!RHC"""""R!Ketone! 1750!–!1660!! Strong!O!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!RHC"""""OH!Carboxylic!Acid! 1725!–!1665! Strong!O!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!RHC"""""OR!!Ester!1775!–!1715! Strong!O!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!RHC"""""N!Amide! 1695!–!1615!!Strong!!N!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!RHC"""""R’!Imine! 1650!–!1550!! Medium!C!!C!Alkene! 1680!–!1600!! Medium!–!weak;!narrow!!Aromatic!~1600!and~1500!–!1430!Medium!–!weak!!TMBare(1/12/201 0)!Bond!Type! Family!Frequency!Range,!!cm"1!Comments!O"""""H! Alcohols! 3600!– 3200 Strong,!broad!N"""""H! Amines,!amides! 3500!–!3200!!Weak – medium.!!1^:!2!bands;!2^:!1!band;!3^:!no!bands!O"""""H! Carboxylic!acid! 3300!–!2500!Strong;!very!broad.!!Usually!strongest!at!~3000!with!gradual!tapering!to!2500!spC"""""H! Alkyne! 3320!– 3300 Strong!–!medium!sp2C"""""H! Alkene,!aromatic! 3100!–!3000!Medium!– weak.!May!be!shoulder!on!stronger!sp3C"H!band!sp3C"""""H! Alkane! 3000!–!2800!!Weak"medium.!!Intensity!proportional!to!number!of!C"H!alkane!bonds!O!!!!RHC"""""H!Aldehyde! 2850!–!2700!!Weak!to!medium,!usually!two!sharp!bands!!1CHM!2202! ! Department!of!Chemistry!Organic!Chemistry!Lab!II! ! Villanova!University!!!!!!Infrared!Absorption!Bands!!Important!CO!Single!Bond!Stret ching!Absorptions!Bond!Type! Family!Frequency!Range,!cm"1!Comments!RH2C"""OH!Primary!Alcohol! 1075!–!1000! Strong!–!medium!!R2HC"""OH!Secondary!Alcohol! 1130!–!1000!! Strong!–!medium!!R3C"""OH!Tertiary!Alcohol! 1210!–!1100! Strong!–!medium!!!Phenol! 1260!–!1180! Strong!O!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!RHC"""""OR!Ester! 1310!–!1160! Strong,!broad!!Important!CH!Bending!Absorptions!Bond!Type! Family!Frequency!Range,!cm"1!Comments!sp3C"""""H!!!! Alkane!1480!– 14301395!–!1340!!!Weak!–!medium!!RCH!!CH2!Monosubstituted!Alkene!997!– 985! and915!"!905!Medium!R2C!!CH2!Disubstituted!terminal!Alkene!895!–!885! Usually!strong!cis"RCH!!CHR’!cis"Alkene! 730!–!665! Usually!strong!trans"RCH!!CHR’!trans"Alkene! 980!–!960! Usually!strong!R2C!!CHR’!Trisubstituted!Alkene!840!–!790! Usually!strong!!Monosubstituted!Benzene!770!– 730!!and720!–!680!Usually!strong!!ortho"Disubstituted!Benzene!770!–!735!Usually!strong!!meta"Disubstituted!Benzene!810!–!750!!and!725!"!680!Usually!strong!!Para"Disubstituted!Benzene!860!"!800!Usually!strong!!Miscellaneous!Diagnostic!Abs or p ti on s!Bond!Type! Family!Frequency!Range,!cm"1!Typical!Absorption!Pattern!Comments!!Monosubstituted!Benzene!2000!–!1650!Weak;!multiple!bands.!Not!always!present.!!!ortho"Disubstituted!Benzene!2000!–!1650!Weak;!multiple!bands.!Not!always!present.!!!meta"Disubstituted!Benzene!2000!–!1650!Weak;!multiple!bands.!Not!always!present.!!!para"Disubstituted!Benzene!2000!–!1650!Weak;!multiple!bands.!Not!always!present.!!TMBare(1/12/201 0)!2CHM 2202 Department of Chemistry Organic Chemistry Lab II Villanova University CHARACTERISTIC CHEMICAL SHIFT VALUES FOR 1H NMR Tabular Display Type of Proton Structure Chemical Shift, ppm Cyclopropane C3H6 0.2 Primary R-CH3 0.9 Secondary R2-CH2 1.3 Tertiary R3-C-H 1.5 Allylic C=C-CH3 1.7 Carbonyl Compounds H-C-C=O 2 – 2.7 Acetylenic 2 – 3 Benzylic Ar-C-HHC C 2 – 2.3 Esters H-C-CO2R 2 – 2.2 Acids H-C-CO2H 2 – 2.6 Ethers H-C-OR 3.3 – 4 Alcohols H-C-OH 3.4 – 4 Esters RCO2-C-H 3.7 – 4.1 Iodides H-C-I 2 – 4 Bromides H-C-Br 2.5 – 4 Chlorides H-C-Cl 3 – 4 Fluorides H-C-F 4 – 4.5 Vinylic C=C-H 4.6 – 5.9 Aromatic Ar-H 6 – 8.5 Amino R-NH2 1 – 5, variable* Hydroxylic R-C-OH 1 – 5.5, variable* Phenolic Ar-OH 4 – 7, variable* Aldehydes 9 - 10 ORCCarboxylic Acids 10 – 12, variable* HORCAmides 5 – 8, variable* OHORCNH2* = Exchanges with D2O 3TMBare(1/12/2010)4<‐‐‐‐/PPM<‐‐‐‐/PPM<‐‐‐‐/PPM56 Approximate Values of Chemical Shifts for 13C NMR Tabular Display_7Graphical