- Using an oxazoline auxiliary group provides steric effect which influences the high diastereoselectivity of asymmetric Ullman reaction.
- Electronegative groups in the ortho position of the aryl halogen are known to be strongly activated toward Ullman reaction.
- Modern variants of the Ullman reaction employing palladium and nickel have widened the substrate scope of the reaction and rendered reaction conditions more mild.
- There are two types of Ullman reaction : Classic ( Copper catalyzed synthesis of symmetric biaryl compounds ) and Ullman type ( copper catalyzed nucleophilic aromatic substitution ).
- It's difficult to find ullman reaction in a sentence. 用ullman reaction造句挺難的