913344-44-2Relevant academic research and scientific papers
Iridium-catalyzed asymmetric allylic substitutions with bulky amines/oxidative double bond cleavage - Entry into the reetz synthesis of amino alcohols
Seehafer, Kai,Malakar, Chandi C.,Bender, Markus,Qu, Jianping,Liang, Chen,Helmchen, Günter
, p. 493 - 501 (2016/02/18)
Branched allylic amines were prepared by Ir-catalyzed enantioselective allylic aminations with the bulky N-nucleophiles HN(Boc)2 and HNBn2. The products were transformed into N-protected amino aldehydes, which were either reduced or coupled diastereoselectively with organometallic compounds to give vicinal amino alcohols. A formal synthesis of the neurokinin receptor antagonist (+)-L-733060 was carried out as an application. Ir-catalyzed enantioselective allylic aminations with bulky N-nucleophiles HN(Boc)2 and HNBn2 gave N-protected allylic amines, which were transformed into N-protected chiral amino aldehydes. These are useful chiral building blocks as previously demonstrated by Reetz et al. A formal synthesis of the neurokinin receptor antagonist (+)-L-733060 was carried out as an application.
Iridium-catalyzed allylic substitutions with cyclometalated phosphoramidite complexes bearing a dibenzocyclooctatetraene ligand: Preparation of (π-Allyl)Ir complexes and computational and NMR spectroscopic studies
Raskatov, Jevgenij A.,Jaekel, Mascha,Straub, Bernd F.,Rominger, Frank,Helmchen, Guenter
, p. 14314 - 14328 (2013/01/15)
(π-Allyl)Ir complexes derived from dibenzocyclooctatetraene and phosphoramidites by cyclometalation are effective catalysts for allylic substitution reactions of linear monosubstituted allylic carbonates. These catalysts provide exceptionally high degrees
Iridium-catalyzed kinetic asymmetric transformations of racemic allylic benzoates
Stanley, Levi M.,Bai, Chen,Ueda, Mitsuhiro,Hartwig, John F.
supporting information; experimental part, p. 8918 - 8920 (2010/08/21)
Versatile methods for iridium-catalyzed, kinetic asymmetric substitution of racemic, branched allylic esters are reported. These reactions occur with a variety of aliphatic, aryl, and heteroaryl allylic benzoates to form the corresponding allylic substitution products in high yields (74-96%) with good to excellent enantioselectivity (84-98% ee) with a scope that encompasses a range of anionic carbon and heteroatom nucleophiles. These kinetic asymmetric processes occur with distinct stereochemical courses for racemic aliphatic and aromatic allylic benzoates, and the high reactivity of branched allylic benzoates enables enantioselective allylic substitutions that are slow or poorly selective with linear allylic electrophiles.
Iridium(I)-catalyzed regio- and enantioselective allylic amidation
Singh, Om V.,Han, Hyunsoo
, p. 7094 - 7098 (2008/03/11)
Ir(I)-catalyzed intermolecular allylic amidation of ethyl allyl carbonates with soft nitrogen nucleophiles under completely 'salt-free' conditions is described. A combination of [Ir(COD)Cl]2, a chiral phosphoramidite ligand L*, and DBU as a base in THF effects the reaction. The reaction appears to be quite general, accommodating a wide variety of R-groups and soft nitrogen nucleophiles, and proceeds with excellent regio- and enantioselectivities to afford the branched N-protected allylic amines. The developed reaction was conveniently utilized in the asymmetric synthesis of N-Boc protected α- and β-amino acids as well as (-)-cytoxazone.
Enantioselective iridium-catalyzed allylic amination of ammonia and convenient ammonia surrogates
Pouy, Mark J.,Leitner, Andreas,Weix, Daniel J.,Ueno, Satoshi,Hartwig, John F.
, p. 3949 - 3952 (2008/02/11)
Iridium-catalyzed, asymmetric allylation of ammonia as a nucleophile occurs with stereoselectivity to form a symmetric dialiylamine, and related allylation of the inexpensive ammonia equivalent potassium trifluoroacetamide or the highly reactive ammonia equivalent lithium ditert-butyliminodicarboxylate forms a range of conveniently protected, primary, a-branched allylic amines in high yields, high branched-to-linear regioselectivities, and high enantiomeric excess. The reactions of ammonia equivalents were conducted with a catalyst generated from a phosphoramidite containing a single stereochemical element.
Salt-free iridium-catalyzed asymmetric allylic animations with N,N-diacylamines and ortho-nosylamide as ammonia equivalents
Weihofen, Robert,Tverskoy, Olena,Helmchen, Guenter
, p. 5546 - 5549 (2007/10/03)
(Chemical Equation Presented) New variants of the iridium-catalyzed allylic substitution allow N-protected and non-protected chiral allylamines to be prepared with high enantio- and regio-selectivity. The allylamines are used as nucleophiles in highly dia
