Structure and Bonding
Esters contain a carbonyl center, which gives rise to 120°C-C-O and O-C-O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C-O-C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. The pKa of the alpha-hydrogens on esters is around 25.
Read more about this topic: Ester
Famous quotes containing the words structure and, structure and/or bonding:
“With sixty staring me in the face, I have developed inflammation of the sentence structure and definite hardening of the paragraphs.”
—James Thurber (18941961)
“Man is more disposed to domination than freedom; and a structure of dominion not only gladdens the eye of the master who rears and protects it, but even its servants are uplifted by the thought that they are members of a whole, which rises high above the life and strength of single generations.”
—Karl Wilhelm Von Humboldt (17671835)
“Attachment to a baby is a long-term process, not a single, magical moment. The opportunity for bonding at birth may be compared to falling in lovestaying in love takes longer and demands more work.”
—T. Berry Brazelton (20th century)