A是醇,B是酸,C是醚,D是酸酐,E是脂
1.2CH3OH=CH3OCH3+H2O
2.2CH3COOH=(CH3CO)2O
3.CH3OH+CH3COOH=CH3COOCH3+H2O
4.(CH3CO)2O+2CH3OH=2CH3COOCH3