Direct enantioselective aldol reactions catalyzed by calix[4]arene-based L-proline derivatives in the water

作者：Eymur Serkan; Akceylan Ezgi; Sahin Ozlem; Uyanik Arzu; Yilmaz Mustafa^*

来源：Tetrahedron, 2014, 70(30): 4471-4477.

DOI：10.1016/j.tet.2014.05.034

• Calix[4]arene
• Organocatalysis
• Aldol
• Water

Two novel p-tert-butylcalix[4]arene-based chiral organocatalysts derived from L-proline have been developed to catalyze direct aldol reactions between cyclohexanone and aromatic aldehydes in water. Under the optimal conditions, high yields (up to 95%), enantioselectivities (up to 90%), and moderate diastereoselectivities (up to 65:35) were obtained. Considering the catalytic inefficiency of sole proline for the aldol reaction in water, these results clearly display the enormous effect of the hydrophobic part of calix[4]arene of compound A.

• 出版日期2014-7-29