69849-15-6Relevant articles and documents
Conversion of ketone trimethylsilylcyanohydrins to several types of compounds
Ohta,Yamashita,Arita,Kajiura,Kawasaki,Noda,Izumi
, p. 1294 - 1301 (2007/10/02)
Cyclic ketone O-trimethylsilylcyanohydrins (2) were prepared and converted to various compounds: α-hydroxyketones (3), dehydroxylated ketones (4), α,β-unsaturated ketones (9), tricyclic ketones (10), 1-ethoxycarbonyl-4- phenyl-1,2,4a,5,6,7,8,8a-octahydro-2-naphthalenone (13), 1- phenylperhydroisocoumarin (18) and 1,2,3,4,4a,10,11,11a-octahydro-5h- benzo[a,d]cyclohepten-10-one (20).
Three-Carbon Annelations. Regiocontrolled Reactivity of Trimethylsilyl- and Ethoxyethyl-Protected Cyanohydrins. Versatile Homoenolate and Acyl Anion Equivalents
Jacobson, Richard M.,Lahm, George P.,Clader, John W.
, p. 395 - 405 (2007/10/02)
The trimethylsilyl- (2) and ethoxyethyl- (4) protected cyanohydrins of α,β-unsaturated aldehydes are utilized as three-carbon annelation reagents.Metalated reagent 2 displays exclusive α reactivity with aldehydes and ketones at -78 deg C.Metalated reagent 4 displays exclusive α reactivity at -78 deg C and exclusive γ reactivity at 0 deg C.Reagent 4 thus allows for complete regiocontrol in its addition to aldehydes and ketones which permits selective addition of either a homoenolate or an acyl anion equivalent.Metalation of the α product 11 at -78 deg C with subsequent warming to 0 deg C produces exclusively the γ product, confirming the reversible nature of the addition to the carbonyl.The derived α '-trimethylsiloxy enones 17 (R3=Me3Si), α '-hydroxy enones 17 (R3=H), α '-acetoxyenones 17 (R3=Ac), and γ-lactones 10 are useful cyclopentenone precursors.Treatment of 17 with p-TsOH in toluene at reflux produces cyclopentenones.The reaction proceeds via the postulated intermediacy of a pentadienyl cation 15 which undergoes in situ electrocyclic ring closure.
