Sequential Suzuki/Asymmetric Aldol and Suzuki/Knoevenagel Reactions Under Aqueous Conditions

• Published in: European journal of organic chemistry 2012-05, Vol.2012 (13), p.2635-2642
• Main Authors: Gruttadauria, Michelangelo, Bivona, Lucia Anna, Lo Meo, Paolo, Riela, Serena, Noto, Renato
• Format: Article
• Language: English
• Subjects: Aldol reactions; Catalysis; Catalysts: preparations and properties; Catalytic reactions; Chemistry; Exact sciences and technology; General and physical chemistry; Heterocyclic compounds; Heterocyclic compounds with only one n hetero atom and condensed derivatives; Homogeneous catalysis; Kinetics and mechanisms; Organic chemistry; Organocatalysis; Palladium; Preparations and properties; Reactivity and mechanisms; Synthetic methods; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 1434-193X; 1099-0690
• DOI: 10.1002/ejoc.201200092

Here we describe for the first time a sequential Suzuki/asymmetric aldol reaction. Such sequential approach was achieved through the combined use of an ionic liquid supported palladium catalyst and the organocatalyst trans‐4‐(2,2‐diphenylacetoxy)proline. Suzuki and asymmetric aldol reactions were performed under aqueous conditions. The use of a palladium catalyst under basic conditions allowed also the first example of sequential Suzuki/Knoevenagel reaction. Reactions were carried out under aqueous conditions and products were isolated in good to high yields and, in the case of the Suzuki/aldol reaction, with diastereoselectivities up to 91:9 and enantioselectivities up to at least 99 %. The first examples of sequential Suzuki/asymmetric aldol and Suzuki/Knoevenagel reactions under aqueous conditions are reported.