title: Sequential column asymmetric catalysis.
abstract: Since the introduction of catalysts and reagents on solid-support, researchers have developed new reaction systems to take advantage of their insoluble nature by designing multistep reaction sequences, high-throughput purification techniques, and combinatorial synthesis methods. The continuous flow system is one of these advancements and represents the foundation of a new technique termed sequential column asymmetric catalysis (CAC). In this strategy, reagents and catalysts are attached to a solid-phase support and loaded onto sequentially-linked columns. The substrates are present in the liquid phase that flows through the column. As a substrate encounters each successive column, it grows in complexity. Consequently, one can imagine a number of flow systems that consist of columns attached in series and/or in parallel that synthesize a fairly complex molecule. Herein, we discuss the development of the sequential CAC technique, beginning with the most relevant antecedents.
authors.affiliation: Department of Chemistry, Johns Hopkins University, 3400 N. Charles St. Baltimore, MD 21218, USA.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Hafez
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Taggi
authors.forename: Thomas
authors.initials: T
authors.lastname: Lectka
mesh_terms: D002384:Catalysis; D002625:Chemistry, Organic / Q000295:instrumentation* / Q000379:methods*; D007659:Ketones / Q000737:chemistry; D007769:Lactams / Q000138:chemical synthesis*
chemical_list: D007659:Ketones; D007769:Lactams