Solvent Properties Nonpolar solutes ether solvates cations: dissolve better in ether than in alcohol RL计 Ether has large dipole R moment, so polar R—O solutes also dissolve R—O4 · Ethers solvate cations RR (not well solvated) RR Ethers do not react with strong bases Chapter 14
Chapter 14 6 Solvent Properties • Nonpolar solutes dissolve better in ether than in alcohol. • Ether has large dipole moment, so polar solutes also dissolve. • Ethers solvate cations. • Ethers do not react with strong bases. =>
Ether Complexes R Grignard reagents O—R H—C—Mg—X R—O Electrophiles : 0-B-H R BH3·THF · Crown ethers > Chapter 14
Chapter 14 7 Ether Complexes • Grignard reagents • Electrophiles • Crown ethers O B H H H + _ BH3 THF =>
Common names of ethers Alkyl alkyl ether Current rule: alphabetical order Old rule: order of increasing complexity Symmetrical: use dialkyl, or just alky EXamples CH CH3-0-C--CH CH3 CH2-O-CH2CH3 CH diethyl ether or ethyl ether t-butyl methyl ether or Chapter 14 methyl t-butyl ether=>
Chapter 14 8 Common Names of Ethers • Alkyl alkyl ether • Current rule: alphabetical order • Old rule: order of increasing complexity • Symmetrical: use dialkyl, or just alkyl. • Examples: CH3 CH2 O CH2 CH3 diethyl ether or ethyl ether CH3 O C CH3 CH3 CH3 t-butyl methyl ether or methyl t-butyl ether =>
UPAC Names ·A| koxy alkane EXamples CH3 O-CH3 CH3-O—C-CH3 CH3 2-methyl-2-methoxypropane Methoxycyclohexane Chapter 14
Chapter 14 9 IUPAC Names • Alkoxy alkane • Examples: CH3 O C CH3 CH3 CH3 2-methyl-2-methoxypropane O CH3 Methoxycyclohexane =>
Cyclic Ethers Heterocyclic: oXygen is in ring Epoxides(oXiranes)H2 C-CH2 Oxetanes Furans (Oxolanes()) O O Pyrans ()(Xanes O) Dioxanes O Chapter 14 10
Chapter 14 10 Cyclic Ethers • Heterocyclic: oxygen is in ring. • Epoxides (oxiranes) H2C CH2 O • Oxetanes O • Furans (Oxolanes ) O O • Pyrans (Oxanes ) O O •Dioxanes O O =>