104937-87-3Relevant academic research and scientific papers
Palladium/BINAP(S)-catalyzed asymmetric allylic amination
Faller,Wilt, Jeremy C.
, p. 633 - 636 (2005)
(Chemical Equation Presented) The enantioselective allylic amination of acyclic allylic carbonates catalyzed by a palladium/(S)-BINAP(S) system was investigated. Amination of several substrates proceeded with high ee. Crotyl carbonates show an unusually high regioselectivity for the branched isomer. The use of (S)-TolBINAP(S) and (S)-3,5-xylyl-BINAP(S) as ligands was found to increase the enantioselectivity of the aminations. A P,S binding mode of the BINAP(S) ligand was found in an X-ray crystallographic study.
Chasing the proton culprit from palladium-catalyzed allylic amination
Dubovyk, Igor,Watson, Iain D. G.,Yudin, Andrei K.
, p. 14172 - 14173 (2007)
We have found that the addition of base has a significant effect on palladium-catalyzed allylic amination. The long-standing problem of controlling the branched-to-linear ratio has been solved. In the presence of DBU and inexpensive, readily available ligands, palladium-catalyzed allylation proceeds under kinetic control, leading to high branched selectivity. Given the widespread utility of palladium-catalyzed allylic amination, we expect that these findings will be relevant in many areas ranging from asymmetric catalysis to target-oriented synthesis. Copyright
A Simple, Broad-Scope Nickel(0) Precatalyst System for the Direct Amination of Allyl Alcohols
Sweeney, Joseph B.,Ball, Anthony K.,Lawrence, Philippa A.,Sinclair, Mackenzie C.,Smith, Luke J.
supporting information, p. 10202 - 10206 (2018/08/06)
The preparation of allylic amines is traditionally accomplished by reactions of amines with reactive electrophiles, such as allylic halides, sulfonates, or oxyphosphonium species; such methods involve hazardous reagents, generate stoichiometric waste streams, and often suffer from side reactions (such as overalkylation). We report here the first broad-scope nickel-catalysed direct amination of allyl alcohols: An inexpensive NiII/Zn couple enables the allylation of primary, secondary, and electron-deficient amines without the need for glove-box techniques. Under mild conditions, primary and secondary aliphatic amines react smoothly with a range of allyl alcohols, giving secondary and tertiary amines efficiently. This “totally catalytic” method can also be applied to electron-deficient nitrogen nucleophiles; the practicality of the process was demonstrated in an efficient, gram-scale preparation of the calcium antagonist drug substance flunarizine (Sibelium).
Achieving control over the branched/linear selectivity in palladium-catalyzed allylic amination
Dubovyk, Igor,Watson, Iain D. G.,Yudin, Andrei K.
, p. 1559 - 1575 (2013/03/28)
Palladium-catalyzed reaction of unsymmetrical allylic electrophiles with amines gives rise to regioisomeric allylic amines. We have found that linear products result from the thermodynamically controlled isomerization of the initially formed branched products. The isomerization is promoted by protic acid and active palladium catalyst. The use of base shuts down the isomerization pathway and allows for the preparation and isolation of branched allylic amines. Solvent plays a key role in achieving high kinetic regioselectivity and in controlling the rate of isomerization. The isomerization can be combined with ring-closing metathesis to afford the synthesis of exocyclic allylic amines from their endocyclic precursors.
Stereoselective synthesis of imidazolidin-2-ones via Pd-catalyzed alkene carboamination. Scope and limitations
Fritz, Jonathan A.,Wolfe, John P.
, p. 6838 - 6852 (2008/09/21)
A method for the synthesis of imidazolidin-2-ones from N-allylureas and aryl or alkenyl bromides via Pd-catalyzed carboamination reactions is described. The N-allylurea precursors are prepared in one step from readily available allylic amines and isocyanates, and the Pd-catalyzed reactions effect the formation of a C-C bond, a C-N bond, and up to two stereocenters in a single step. Good diastereoselectivities are obtained for the conversion of substrates bearing allylic substituents to 4,5-disubstituted imidazolidin-2-ones, and excellent selectivity for the generation of products resulting from syn-addition across the alkene is observed when substrates derived from cyclic alkenes or E-1,2-disubstituted alkenes are employed. A brief discussion of reaction mechanism and product stereochemistry is presented.
Investigations concerning the organolanthanide and group 3 metallocene-catalyzed cyclization-functionalization of nitrogen-containing dienes
Molander, Gary A.,Romero, Jan Antoinette C.
, p. 2631 - 2643 (2007/10/03)
Organolanthanide catalyzed cyclization-silylation of nitrogen-containing polyunsaturated systems allows access to core structures commonly found in naturally occurring alkaloids. Nitrogen-containing dienes with various substitution patterns were investigated. The method was most successful for substrates with terminal alkenes. Cyclization upon pendant 1,1-disubstituted olefins was not realized under various conditions. Interestingly, sterically hindered sulfonamides, which were previously believed to render the catalyst inactive, were actually compatible with the catalyst, thus affording the cyclized products after prolonged reaction times. Variations using fused ring systems were also investigated.
Substitution reactions of hindered cyclic sulfamidates
Posakony, Jeffrey J.,Tewson, Timothy J.
, p. 859 - 864 (2007/10/03)
Five- and six-membered cyclic sulfamidates, [1,2,3]-oxathiazolidineand [1,2,3]-oxathiazinane-2,2-dioxides, with the leaving group oxygen at sterically hindered centers were synthesized and treated with selected nucleophiles (azide, cyanide, fluoride, butylamine, sec-butylamine, tert-amylamine, and imidazole) in substitution reactions to demonstrate the general utility and limitations of these substrates. Substitutions adjacent to quaternary carbon centers were accomplished with relative ease. In contrast to the 4,4-dimethyl substituted 5-membered sulfamidate 1, which reacted with the entire set of nucleophiles, the more hindered 5-membered and 6-membered sulfamidates (7 and 6, respectively) reacted only with the first few of this set.
The [2,3] sigmatropic rearrangement of N-benzyl-O-allylhydroxylamines
Davies, Stephen G.,Fox, John F.,Jones, Simon,Price, Anne J.,Sanz, Miguel A.,Sellers, Thomas G. R.,Smith, Andrew D.,Teixeira, Fatima C.
, p. 1757 - 1765 (2007/10/03)
The rearrangement of a range of N-benzyl-O-allylhydroxylamines to the corresponding N-allylhydroxylamines upon treatment with n-BuLi in THF, followed by reduction to the corresponding N-allylamines, is described. Mechanistic studies of the transformation are consistent with an intramolecular [2,3] sigmatropic rearrangement.
A novel [2,3] intramolecular rearrangement of N-benzyl-O-allylhydroxylamines
Davies, Stephen G.,Jones, Simon,Sanz, Miguel A.,Teixeira, Fatima C.,Fox, John F.
, p. 2235 - 2236 (2007/10/03)
A novel [2,3]-sigmatropic rearrangement whereby N-benzyl-O-allylhydroxylamines undergo transformation to the corresponding N-allylhydroxylamines, which can subsequently be reduced to the corresponding allylamines, is described and evidence for the intramolecular nature of this process presented.
Transition Metal-Catalyzed Radical Cyclizations: A Low-Temperature Process for the Cyclization of N-Protected N-Allyltrichloroacetamides to Trichlorinated γ-Lactams and Application to the Stereoselective Preparation of β,γ-Disubstituted γ-Lactams
Nagashima, Hideo,Ozaki, Nobuyasu,Ishii, Masayuki,Seki, Koji,Washiyama, Masayoshi,Itoh, Kenji
, p. 464 - 470 (2007/10/02)
Cyclisations of N-substituted N-allyltrichloroacetamides, where the substituent is an alkyl, Cbz, Boc, Ts, or Ms group, are catalyzed by a 1:1 mixture of CuCl and bipyridine to give the corresponding β,γ-trichlorinated γ-lactams in high yields.The reactions proceed at temperatures from -78 deg C to room temperature.Cyclizations of N-allyltrichloroacetamides of acyclic secondary allylic amines are achieved with good selectivity; the cis/trans ratios of the γ-lactams formed were dependent on the substituents on the nitrogen atom.The stereochemical outcome is compared with that of free-radical cyclization.
