Robust and Efficient, Yet Uncatalyzed, Synthesis of Trialkylsilyl-Protected Cyanohydrins from Ketones
作者:Fabien L. Cabirol、Angela E. C. Lim、Ulf Hanefeld、Roger A. Sheldon、Ilya M. Lyapkalo
DOI:10.1021/jo702587e
日期:2008.3.1
High-yielding cyanosilylation of ketones with NaCN and various chlorotrialkylsilanes in DMSO proceeds smoothly without catalysis to give silyl-protected ketone cyanohydrins. The unique role of DMSO consists in rendering naked cyanide anions that reversibly add to the CO bond at the rate-determining step followed by fast trapping of the transient tertiary sodium cyanoalcoholates with chlorotrialkylsilanes
Dienediolates of unsaturated carboxylic acids in synthesis. Synthesis of cyclohexenones and polycyclic ketones by tandem Michael-Dieckmann decarboxylative annulation of unsaturated carboxylic acids.
作者:María J. Aurell、Pablo Gaviña、Ramon Mestres
DOI:10.1016/s0040-4020(01)86973-8
日期:1994.2
Substituted 2-cyclohexenones 4 to 7 and hexaxydronaphthalenones and hexahydroindenones 13 to 18 are prepared by tandem Michael-Dieckmann addition of lithium dienediolates of acyclic and alicyclic unsaturated carboxylic acids to the lithium salts of the same or other unsaturated carboxylic acids.
STRUCTURE AND PROPERTIES OF CYCLIC COMPOUNDS: XI. DISSOCIATION CONSTANTS OF THE CYANOHYDRINS OF SOME METHYLCYCLOHEXANONES
作者:Owen H. Wheeler、Jacob Z. Zabicky
DOI:10.1139/v58-091
日期:1958.4.1
The dissociationconstants of the cyanohydrins of a series of methylcyclohexanones have been measured. The polymethylcyclohexanone cyanohydrins show increasing instability on substitution owing to the effects of "axial crowding". The cyanohydrins of 3- and 4-methylcyclohexanone were found to be more stable than that of cyclohexanone and to explain this a new concept of "equatorial interference" is
The synthetic utility of N-heterocyclic carbenes was demonstrated by the trialkylsilylcyanation of aldehydes, ketones and imines. In the presence of a catalytic amount of 3a, the reactions with Me3SiCN proceeded smoothly to give the corresponding cyanohydrin trimethylsilyl ethers or amino nitrile derivatives in good to excellent yields.