Diastereoselection in the LiA1H4 reduction of severely hindered β-diketones examples of -curtin-hammett preequilibrium conditions
摘要:
LiAlH4 Reduction of alpha-adamantyl (and tert-butyl)-beta-diketones occur under anti-Curtin-Hammett preequilibrium conditions, each preferred conformer leading to a different stereoisomeric diol, whereas reduction of 3-adamantyl-3-methyl (and ethyl)pentane-2,4-dione occurs with high diastereoselectivity to afford only the (2R, 3r, 4S) meso diol.
Catalytic Allylic Alkylation via the Cross-Dehydrogenative-Coupling Reaction between Allylic sp3 C−H and Methylenic sp3 C−H Bonds
摘要:
A catalytic allylic alkylation was developed via the cross-dehydrogenative-coupling reaction of allylic sp3 C-H and methylenic sp3 C-H catalyzed by copper bromide and cobalt chloride in the presence of an oxidizing reagent, t-BuOOH. This methodology provides a direct way to use allylic sp3 C-H bonds for forming C-C bonds.