18322-82-2Relevant academic research and scientific papers
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.
Synthesis of aryl alkyl ethers by alkylation of phenols with quaternary ammonium salts
Maras, Nenad,Polanc, Slovenko,Kocevar, Marijan
experimental part, p. 29 - 36 (2010/09/05)
Phenolic compounds can be efficiently O-methylated with tetramethylammonium chloride in diglyme or polyethyleneglycol (PEG) at temperatures of 150-160 °C and in the presence of either K2CO3 or NaOH. When applying benzyl-trimethylammonium chloride as a reagent, the benzylation and methylation of phenols occurs, with the benzylation product always predominating. With allyl-substituted phenols as substrates and using NaOH as a base it was possible to achieve both the alkylation and the double-bond isomerization of the allyl group to obtain (E/Z)-propenyl-substituted methyl and benzyl aryl ethers in a single preparative step.
Asymmetric cross-coupling of potassium 2-butenyltrifluoroborates with aryl and 1-alkenyl bromides catalyzed by a Pd(OAc)2/Josiphos complex
Yamamoto, Yasunori,Takada, Shingo,Miyaura, Norio
, p. 1368 - 1369 (2007/10/03)
The asymmetric cross-coupling reaction of [CH3CH= CHCH 2BF3]K with aryl or 1-alkenyl bromides selectively occurred at the γ-carbon of 2-butenylborane moiety with regioselectivities in a range of 84-99%. The enantioselectiv
A new direct allylation of the aromatic compounds with allylic chlorides catalyzed by indium metal
Lim, Hwan Jung,Keum, Gyochang,Kang, Soon Bang,Kim, Youseung,Chung, Bong Young
, p. 1547 - 1550 (2007/10/03)
A new method of the direct allylation reaction for the aromatic compounds with allylic chlorides using a catalytic mount of indium in the presence of CaCO3/4A molecular sieves was developed.
α-Selective cross-coupling reaction of allyltrifluorosilanes: Remarkable ligand effect on the regiochemistry
Hatanaka, Yasuo,Goda, Ken-Ichi,Hiyama, Tamejiro
, p. 6511 - 6514 (2007/10/02)
The cross-coupling reaction of allyltrifluorosilanes with aryl halides or aryl triflates promoted by a fluoride salt takes place at the α-carbon of the allyltrifluorosilanes in the presence of a catalytic amount of PdCl2[Ph2P(CH
Synthesis and Reactions of Allylic and Homoallylic Pyrophosphate Tetraesters
Butsugan, Yasuo,Nagai, Kenji,Nagaya, Fumitoshi,Tabuchi, Hiroki,Yamada, Katsuhisa,Araki, Shuki
, p. 1707 - 1714 (2007/10/02)
Pyrophosphate tetraesters possessing allylic and homoallylic side chains were synthesized.Reaction of alkyl allyl (and 3-methyl-3-butenyl) phosphorochloridates with sodium hydrogencarbonate gave P1,P2-dialkyl P1,P2-diallyl and P1,P2-bis(3-methyl-3-buteny
Method for converting unsaturated compound having functional group
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, (2008/06/13)
A method for the conversion of an unsaturated compound having a functional group, characterized by contacting [1] at least one compound selected from the group consisting of carboxylic acid esters, nitriles, ketones, amides, and ethers and having a carbon-to-carbon double bond and no unsaturation at the position conjugate to said double bond, or a mixture of said compound [1] and [2] at least one compound selected from the group consisting of ethylenically unsaturated compounds having a carbon-to-carbon double bond and neither unsaturation at the position conjugate to said double bond nor a functional group, with a catalyst system consisting essentially of a combination of (A) at least one member selected from the group consisting of tungsten compounds, molybdenum compounds, and rhenium compounds, with (B) at least one organoaluminum compound having at least one carbon-to-aluminum bond.
