Vinyl-group-electron-withdrawing, an electron withdrawing group will have the opposite effect on the nucleophilicity of the ring. the ewg removes electron density from a π system, making it less reactive in this type of reaction, and therefore called deactivating groups. edgs and ewgs also determine the positions on the aromatic ring where substitution reactions are most likely to take place; this property is therefore important in processes of organic synthesis. electron donating groups are generally ortho/para .... 1. substituents with lone pairs (e.g.-och 3, -nh 2) on the atoms adjacent to the p system are electron donating groups (edg)-they activate the aromatic ring by increasing the electron density on the ring through a resonance donating effect.the resonance effect only allows electron density to be positioned at the ortho-and para-positions., i'm assuming that you are talking about groups on an aromatic ring. electron donating groups (after drawing the structure of the compound) have lone pairs of electrons on the atom that is bonded to the ring; they donate electrons to the ring by resonance..
Aryl groups are widely employed as the protector. some kinds of phenyl derivatives can be removed by basic hydrolysis. the removal, particularly from phosphodiesters, frequently requires high temperature. 134,135 for example, the 4-chloro-2-nitrophenyl ester (106; equation 63) is hydrolyzed by sodium hydroxide at 100 °c. 136 similarly, hydrolysis of the 2-chloromethyl-4-nitrophenyl analog ..., chain polymerization study guide by jserrano727 includes 50 questions covering vocabulary, terms and more. quizlet flashcards, activities and games help you improve your grades.