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Narzędzia chemii kombinatorycznej. Cz. 4. Synteza asymetryczna na fazie stałej

Łaźny R., Nodzewska A., Żabicka B.

Wiadomości Chemiczne

2006

[Z] 60, 3-4

191-255

Solid Phase Asymmetric Synthesis (SPOS) is a recently introduced term embracing all methods of asymmetric synthesis involving use of solid supported substrates and reagents. This review presents basic definitions of asymmetric synthesis and currently used concepts for enatioselective and diastereoselective transformations involving supported synthesis. The concepts of chiral auxiliary, chiral catalyst and chiral reagent are illustrated with selected but fairly comprehensive overview of methods published till January 2005. In particular use of chiral auxiliaries such as oxazolidine derivatives, amines, hydrazines, sulfoxides, sulfinyl amides, sulfoxy imines, carbohydrates and alcohols is covered. Applications of immobilized chiral catalysts to synthesis of carbon-carbon bonds, carbon-hydrogen bonds, carbon--heteroatom bonds and in phase-transfer catalysis is presented with selected reactions due to huge volume of literature in this field. Moreover applications of chiral catalysts and chiral reagents in reactions of immobilized substrates and use of chiral immobilized reagents is also reviewed. The literature review shows that the most popular methods of supported asymmetric synthesis are the alkylation of enolates, aldol reactions, Grignard reactions, cycloadditions, reduetion of ketones, epoxida-tions, olefin dihydroxylation, and phase-transfer catalyzed reactions. There are numerous applications of immobilized chiral catalysts and a substantial number of applications of immobilized chiral auxiliaries. On the other hand there are only scarce reports of applications of chiral reagents and chiral catalysts to the reactions of achiral immobilized substrates.

Narzędzia chemii kombinatorycznej. Cz 3. Reakcje w syntezie organicznej na fazie stałej

Łaźny R., Łapińska M., Sienkiewicz M.

Wiadomości Chemiczne

2005

[Z] 59, 11-12

881--952

Solid Phase Organic Synthesis (SPOS) is a dynamically growing branch of organic synthesis encompusing methods for synthesis of both small molecules and oligomers on solid supports. Synthetically useful organic reactions of substrates immobilized on solid supports constitute a central part of the methodology of solid phase synthesis. This review article presents a representative and fairly comprehensive overview of reactions of supported substrates published till January 2005. The reactions are classified in synthetic terms into functional group interconvertions (FG1, according to type of functional group reacting and prepared) and C-C bond forming reactions (according to reaction type; usually name reaction). Fn particular preparations of halogens, alcohols, ethers, thiols, aldehydes, ketones, acids, esters, amides, phosphines, amines, poliamines, peptides, peptoids, oligonucleotides, and oligosaccharides is covered. Oxidation reactions of alcohols, aldehydes and ketones as well as reduction reactions of aldehydes, ketones, esters, acids, nitro and nitroso compounds are also presented. Only the selected reactions used for preparation of oligonucleotides, oligosaccharides, and polypeptides are covered due to the large volume of literaturę on this topie. The important C-C bond forming reactions such as Mannich, Michael, aldol, Heck, Suzuki, Stille, Sonogashira, Wittig, Horner-Wad-sworth-Emmons, metathesis, carbonyl compound alkylation and acylation reactions are illustrated with examples. Moreover the multicomponent reactions such as Ugi reaction, Hantzsch reaction and Baylis-Hillman reaction are also included in the review. The literature review shows a spectrum of synthetic organic reactions which can be performed on the immobilized substrates and suggests that in principle every reaction could be performed on solid phase. Howeverthe literature review indicates that reactions of polar organometallic reagents, radical reactions, and enantioselective reactions of achiral immobilized substrates are rather rarely used in SPOS.