An Efficient [4 + 2 + 1] Entry to Seven-Membered Rings
作者:Yike Ni、John Montgomery
DOI:10.1021/ja046147y
日期:2004.9.1
A new nickel-catalyzed procedure for the [4 + 2 + 1] cycloaddition of trimethylsilyl diazomethane with alkynes tethered to dienes has been developed. A broad range of unsaturated substrates participate in the sequence, and stereoselectivities are generally excellent. Three possible mechanisms are proposed, and each involves the generation of a transient nickel carbene species.
Studies directed toward the total synthesis of the rubradirin antibiotics. 5. A convenient preparation of functionalized isoprene units for the diels-alder reaction
作者:Alan P. Kozikowski、Yoshinori Kitigawa
DOI:10.1016/s0040-4039(00)87268-8
日期:1982.1
Synthetic Studies and Mechanistic Insight in Nickel-Catalyzed [4+2+1] Cycloadditions
作者:Yike Ni、John Montgomery
DOI:10.1021/ja057741q
日期:2006.3.1
with alkynes tethered to dienes has been developed. A broad range of unsaturated substrates participate in the sequence, and stereoselectivities are generally excellent. Stereochemicalstudies provided evidence for a mechanism that involves the [3,3] sigmatropicrearrangement of divinylcyclopropanes.
Asymmetric Catalytic Reductive Coupling of 1,3-Enynes and Aromatic Aldehydes
作者:Karen M. Miller、Elizabeth A. Colby、Katrina S. Woodin、Timothy F. Jamison
DOI:10.1002/adsc.200505175
日期:2005.10
Nickel-catalyzed reductive coupling reactions of 1,3-enynes and aromaticaldehydes efficiently afford conjugated dienols in excellent regioselectivity and modest enantioselectivity when conducted in the presence of catalytic amounts of a monodentate, P-chiral ferrocenyl phosphine ligand. 1-(Trimethylsilyl)-substituted enynes are shown to be effective coupling partners in these reactions, and the dienol products