Mechanistic Dichotomy in CpRu(CH<sub>3</sub>CN)<sub>3</sub>PF<sub>6</sub> Catalyzed Enyne Cycloisomerizations
作者:Barry M. Trost、F. Dean Toste
DOI:10.1021/ja012450c
日期:2002.5.1
Enynes are easily accessible building blocks as a result of the rich chemistry of alkynes and thus represent attractive substrates for ring formation. A ruthenium catalyst for cycloisomerization effects such reaction of 1,6- and 1,7-enynes typically at room temperature in acetone or DMF under neutral conditions. The reaction is effective for forming five- and six-membered rings of widely divergent
Intramolecular Cyclopropanation of Unsaturated Terminal Epoxides and Chlorohydrins
作者:David M. Hodgson、Ying Kit Chung、Irene Nuzzo、Glòria Freixas、Krystyna K. Kulikiewicz、Ed Cleator、Jean-Marc Paris
DOI:10.1021/ja0672932
日期:2007.4.1
Lithium 2,2,6,6-tetramethylpiperidide (LTMP)-induced intramolecular cyclopropanation of unsaturated terminal epoxides provides an efficient and completely stereoselective entry to bicyclo[3.1.0]hexan-2-ols and bicyclo[4.1.0]heptan-2-ols. Further elaboration of C-5 and C-6 stannyl-substituted bicyclo[3.1.0]hexan-2-ols via Sn-Li exchange/electrophile trapping or Stille coupling generates a range of substituted
The present application relates to perfume raw materials, perfume delivery systems and consumer products comprising such perfume raw materials and/or such perfume delivery systems, as well as processes for making and using such perfume raw materials, perfume delivery systems and consumer products. Such perfume raw materials and compositions, including the delivery systems, disclosed herein expand the perfume communities' options as such perfume raw materials can provide variations on character and such compositions can provide desired odor profiles.
Secondary Products from Intramolecular Cycloadditions of Azidoalkyl Enol Ethers and Azidoalkyl Vinyl Bromides: 1-Azadienes, Their Reactions with Diphenylketene, and Radical Cyclizations To Form Bi- and Tricyclic Lactams
作者:John T. R. Liddon、Peter J. Lindsay-Scott、Jeremy Robertson
DOI:10.1021/acs.joc.9b02005
日期:2019.11.1
cycloadducts formed by heating analogous azidoalkyl vinyl bromides are unstable with respect to elimination of N2 and HBr, affording 1-azadienes (2-alkenyl cyclic imines). These primary products may be isolated or treated directly with diphenylketene to produce bi- and tricyclic 3,4-dihydropyridin-2(1H)-ones; similar ring systems may also be produced from the azadienes by N-acylation and radical cyclization
A new methodology of intramolecular hetero Diels–Alder reaction with β-alkoxy-substituted conjugated nitroalkenes as heterodienes: stereoselective one-pot synthesis of trans-fused bicyclic γ-lactones
作者:Eiji Wada、Masahiko Yoshinaga
DOI:10.1016/j.tetlet.2003.08.106
日期:2003.10
Tandem reaction of (E)-1-ethoxy-2-nitroethylene with δ,ε-unsaturated alcohols leading to stereoselective trans-fused bicyclic γ-lactones has been developed using a catalytic amount of a Lewis acid such as Yb(OTf)3 and Ni(ClO4)2·6H2O. This process involves the stereoselective tandem transetherification–intramolecular heteroDiels–Alderreaction leading to bicyclic nitronates, and sequential transformation