15324-90-0Relevant articles and documents
Volatile non-terpenoid hydrocarbons from Ligusticum grayi roots
Cool, Laurence G.,Takeoka, Gary R.,Vermillion, Karl E.
, p. 158 - 160 (2011)
The root essential oil of Ligusticum grayi Coult. & Rose (Apiaceae) was found to contain three volatile non-terpenoid hydrocarbons: the known C 11 compound viridene, whose structure is hereby corrected to 1-[(2Z)-pent-2-en-1-yl]cyclohexa-1,3-diene; and the heretofore unreported C 10 compounds 1-[(2Z)-but-2-en-1-yl]cyclohexa-1,3-diene (norviridene), and (Z)-but-2-en-1-ylbenzene (ar-norviridene). These compounds are structurally similar to the 3-alkylphthalides that are widespread in the Apiaceae and, like the latter, probably arise from polyketide precursors.
Comtet
, p. 5308,5310 (1970)
Double-Bond Isomerization: Highly Reactive Nickel Catalyst Applied in the Synthesis of the Pheromone (9 Z,12 Z)-Tetradeca-9,12-dienyl Acetate
Weber, Felicia,Schmidt, Anastasia,R?se, Philipp,Fischer, Michel,Burghaus, Olaf,Hilt, Gerhard
, p. 2952 - 2955 (2015)
A highly reactive nickel catalyst comprising NiCl2(dppp) or NiCl2(dppe) with zinc powder, ZnI2 and Ph2PH, was applied in the isomerization of terminal alkenes to Z-2-alkenes. The double-bond geometry of the 2-alkene can be controlled via the reaction temperature to yield the 2-Z-alkenes in excellent yields and high Z-selectivities. The formation of other constitutional isomers, such as 3-alkenes, is suppressed on the basis of the proposed mechanism via a 1,2-hydride shift from the metal to the Ph2P ligand. The nickel-catalyzed isomerization reaction was then applied in the synthesis of (9Z,12Z)-tetradeca-9,12-dienyl acetate, a pheromone with a 2Z,5Z-diene subunit.
Selecting double bond positions with a single cation-responsive iridium olefin isomerization catalyst
Camp, Andrew M.,Kita, Matthew R.,Blackburn, P. Thomas,Dodge, Henry M.,Chen, Chun-Hsing,Miller, Alexander J.M.
supporting information, p. 2792 - 2800 (2021/03/01)
The catalytic transposition of double bonds holds promise as an ideal route to alkenes of value as fragrances, commodity chemicals, and pharmaceuticals; yet, selective access to specific isomers is a challenge, normally requiring independent development of different catalysts for different products. In this work, a single cation-responsive iridium catalyst selectively produces either of two different internal alkene isomers. In the absence of salts, a single positional isomerization of 1-butene derivatives furnishes 2-alkenes with exceptional regioselectivity and stereoselectivity. The same catalyst, in the presence of Na+, mediates two positional isomerizations to produce 3-alkenes. The synthesis of new iridium pincer-crown ether catalysts based on an aza-18-crown-6 ether proved instrumental in achieving cation-controlled selectivity. Experimental and computational studies guided the development of a mechanistic model that explains the observed selectivity for various functionalized 1-butenes, providing insight into strategies for catalyst development based on noncovalent modifications.
Tandem Olefin Isomerization/Cyclization Catalyzed by Complex Nickel Hydride and Br?nsted Acid
Kathe, Prasad M.,Caciuleanu, Alexandru,Berkefeld, Andreas,Fleischer, Ivana
, p. 15183 - 15196 (2020/11/30)
We disclose a nickel/Br?nsted acid-catalyzed tandem process consisting of double bond isomerization of allyl ethers and amines and subsequent intramolecular reaction with nucleophiles. The process is accomplished by [(Me3P)4NiH]N(SO2CF3)2 in the presence of triflic acid. The methodology provides rapid access to tetrahydropyran-fused indoles and other oxacyclic scaffolds under very low catalyst loadings.
