In Fig. 25.2, the C—O—P bond angle (118°) suggests that the oxygen is sp²-hybridized. Use resonance structures to show why this hybridization and geometry is reasonable.

Transcribed Image Text:

1.50 Å H₂C 114⁰ 99.2° 1.78 Å (a) 1.80 Å methyl thioacetate CH3 H₂C. 1.42A 126.5% O 107° 1.34Å O 1.42Å trimethyl carbonate CH3 H₂C 1.43 Å 118⁰ O 114% (b) FIGURE 25.2 A comparison of the structures of (a) a thioester, (b) a carboxylic acid ester, and (c) a phosphate ester. In comparing the thioester and the oxygen ester, notice that the lengths of the two carbon-sulfur bonds of the thioester are nearly the same, whereas the lengths of the two carbon-oxygen bonds of the oxygen ester are significantly different. In the phosphate ester, notice the tetrahedral structure and the relative bond lengths of the phosphorus-oxygen double and single bonds. 1.58 A 105° trimethyl phosphate (c) OCH3 OCH3