122981-06-0Relevant articles and documents
Synthesis of Highly Oxygenated Carbocycles by Stereoselective Coupling of Alkynes to 1,3- and 1,4-Dicarbonyl Systems
Kier, Matthew J.,Leon, Robert M.,O'Rourke, Natasha F.,Rheingold, Arnold L.,Micalizio, Glenn C.
, p. 12374 - 12377 (2017/09/23)
Densely substituted and highly oxygenated carbocycles are challenging targets for synthesis. In particular, those possessing numerous contiguous, fully substituted carbon atoms (i.e., tertiary alcohols and quaternary centers) are often not accessible in a direct fashion, necessitating the strategic decoupling of ring-formation from the establishment of functionality about the system. Here, we describe an approach to the construction of highly oxygenated mono-, di-, and polycyclic carbocycles from the reaction of disubstituted alkynes with β- or γ-dicarbonyl systems. These processes embrace a variant of metallacycle-mediated annulation chemistry where initial alkyne-carbonyl coupling is followed by a second, now intramolecular, stereoselective C-C bond-forming event. In addition to revealing the basic reactivity pattern in intermolecular settings, we demonstrate that this class of reactivity is quite powerful in a fully intramolecular context and, when terminated by a stereoselective oxidation process, can be used to generate polycyclic systems containing a fully substituted and highly oxygenated five-membered ring.
Organocatalytic Redox Isomerization of Electron-Deficient Allylic Alcohols: Synthesis of 1,4-Ketoaldehydes
Mondal, Keshab,Mondal, Buddhadeb,Pan, Subhas Chandra
, p. 4835 - 4840 (2016/07/06)
An organocatalytic redox isomerization strategy has been developed for the synthesis of 1,4-ketoaldehydes. DABCO was found to be the best catalyst for the isomerization of -hydroxy enones. With 20 mol % of DABCO as catalyst and DMSO as the solvent high yi
Catalytic Asymmetric Synthesis of γ-Hydroxy Ketones and Aromatic Hydroxy Ketones by the Chemo- and Enantio-selective Alkylation of keto Aldehydes with Dialkylzincs
Watanabe, Masami,Soai, Kenso
, p. 3125 - 3128 (2007/10/02)
Optically active γ-hydroxy ketones and aromatic hydroxy ketones with high (up to 96percent) enantiomeric excesses have been synthesized by the chemo- and enantio-selective addition of dialkylzincs to γ-keto aldehydes and aromatic keto aldehydes, respectively, using N,N-dibutylnorephedrine (DBNE) 1 and (1-methylpyrrolidin-2-yl)diphenylmethanol (DPMPM) 5 as chiral catalysts.The method provides a non-homoaldol approach to optically active γ-hydroxy ketones.
