O2H CO2H C(CH3)3 OCH OCH3 C(CH3)3 (H3C)3C 9. Match the underlined protons in the following compounds with the correct chemical shift: Spectrometric Identification of Organic Compounds, Fifth Edition) (a) H3C HC CH H3 (c)H3C—cH20—CH3 1.20();2.40(),5.30()8.21()5.00(),6.73()(1) CH3 CH3 CO2H C(CH3)3 CO2H (2) OCH3 OCH3 OCH3 C(CH3)3 OCH3 O2N (3) CH(CH3)2 CO2H SO3H (4) C (H3C)3C H3C O 9．Match the underlined protons in the following compounds with the correct chemical shift: ( Spectrometric Identification of Organic Compounds, Fifth Edition) (a) H3C HC CH CH3 (b) C O CH3 (c) H3C CH2 O CH3 (d) C C H H3C COOCH3 CH3 (e) NO2 H (f) CH2OCCH3 O 1.20 ( ) ; 2.40 ( ); 5.30 ( ); 8.21 ( ); 5.00 ( ); 6.73 ( )