MacMillan’s imidazoline

Scheme 33.3 General synthesis for MacMillan s imidazoline catalyst.

Organocatalysis in combination with oxidants enables intramolecular asymmetric a-arylation of carbonyl compounds. In 2009, Nicolaou and MacMillan independently reported asymmetric a-arylation of aldehydes (Scheme 7.15). Using MacMillan s imidazoline catalyst and an appropriate... 

The potential of chiral secondary amines in iminium catalysis [45], exemplified by MacMillan s imidazoline catalyst, [46,47] have been well demonstrated in the reactions involving a,p-unsaturated aldehydes. However, the success with deployment of a,P-unsaturated ketones or a-substituted enals have been quite limited, presumably due to the steric hindrance in forming iminium intermediates with secondary amines. In this context, chiral primary amines have recently emerged as viable and powerful catalysts for these challenging substrates. 

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