18018-02-5Relevant academic research and scientific papers
Diastereoselective Palladium-Catalyzed Conjugate Addition of Arylboronic Acids to α-Substituted Cyclic Enones
Gao, Ang,Liu, Xiu-Yan,Ding, Chang-Hua,Hou, Xue-Long
supporting information, p. 2829 - 2832 (2017/10/07)
A palladium-catalyzed conjugate addition of arylboronic acids to α-substituted cyclic enones was developed to give α,β-disubstituted ketones with high diastereoselectivity. Mechanistic investigation showed that the high diastereoselectivity was realized through epimerization.
The α-Effect in the Stereochemistry of Kinetic Ketonization of Enols
Zimmerman, Howard E.,Wang, Pengfei
, p. 9226 - 9232 (2007/10/03)
Kinetic control of the stereoselectivity of protonation of enolates and other strongly delocalized anionic species is involved in a large number of organic reactions. Protonation occurring from the less hindered side of the, e.g., enolic system affords the less stable of two diastereomers. However, one apparent discrepancy has been in the synthesis of prostaglandins. The present research deals with the source of this behavior. A curious effect of the substituent at the enolic α carbon was uncovered. In certain instances an α substituent is forced to twist into a conformation blocking the proton donor from its side, thus reversing the stereochemistry of protonation. In the course of this research, a number of five-ring enols of varying structure were investigated. Finally, the ketonization reaction course has been studied theoretically.
Ultrasound in Organic Synthesis. 7. Preparation of Organozinc Reagents and Their Nickel-Catalyzed Reactions with α,β-Unsaturated Carbonyl Compounds
Petrier, Christian,Barbosa, Jayne C. de Souza,Dupuy, Claude,Luche, Jean-Louis
, p. 5761 - 5765 (2007/10/02)
Diorganozinc compounds can be prepared with great ease and efficiency in a one-pot process, by sonication of lithium, an organic halide, and a zinc halide in THF or toluene mixtures.The reagents thus obtained give rise to clean and selective conjugate additions to α,β-unsaturated aldehydes and ketones in the presence of catalytic amounts of nickel acetylacetonate.
SYNTHESIS OF COMPOUNDS OF THE trans-3,4,4a,9,10,10a-HEXAHYDRO-10a-METHYLPHENANTHRENE SERIES - INTERMEDIATE PRODUCTS IN THE TOTAL SYNTHESIS OF D-HOMOSTEROIDS
Shner, V. F.,Turchin, K. F.,Sheinker, Yu. N.,Suvorov, N. N.
, p. 37 - 41 (2007/10/02)
A stereospecific method was developed for the production of compounds of the trans-3,4,4a,9,10,10a-hexahydro-10a-methylphenanthrene - tricyclic intermediates in the total synthesis of D-homosteroids.
