119793-72-5Relevant academic research and scientific papers
Kinetic resolution in Pd-catalyzed allylic substitution using the helical PHelix ligand
Reetz, Manfred T.,Sostmann, Stefan
, p. 105 - 109 (2000)
The chiral helical diphosphine 2,15-bis(diphenylphosphino)-hexahelicene (PHelix) is an excellent ligand in palladium catalyzed kinetic resolution involving allylic substitution. Depending upon the substrate, enantioselectivities (ee) of up to 99% are observed. Although formally a diphosphine, PHelix appears not to undergo chelation, which means that it behaves as a chiral monophosphine.
Enantioselective molybdenum-catalyzed allylic alkylation using chiral bisoxazoline ligands
Glorius, Frank,Pfaltz, Andreas
, p. 141 - 144 (1999)
(equation presented) 54-86% yield R = Ph, Pr, CH3, OCH3, OPh 76 to 99% ee of A A : B = 8 : 1 up to >20 : 1 A series of chiral C2-symmetric bisoxazolines with trans-1,2-diaminocyclohexane backbones was synthesized. In view
Metallated Container Molecules: A Capsular Nickel Catalyst for Enhanced Butadiene Polymerisation
Elaieb, Fethi,Sameni, Soheila,Awada, Mouhamad,Jeunesse, Catherine,Matt, Dominique,Toupet, Loic,Harrowfield, Jack,Takeuchi, Daisuke,Takano, Shigenaga
, p. 4690 - 4694 (2019)
A unique, covalently constructed capsular catalyst obtained by reaction of [Ni(η5-C5H5)(1,5-cyclooctadiene)] BF4 with the double-calixarene-derived diphosphine 1,3-bis(5-diphenylphosphino-25,26,27,28-tetrapropoxycalix[4]aren-17-yl)benzene (1) has been shown to polymerise butadiene at a rate considerably superior to that of previously known catalysts. The reported results indicate that the container structure of the covalent complex is retained during catalysis.
Derivatives of 2-amino-2′-diphenylphosphino-1,1′-binaphthyl (MAP) and their application in asymmetric palladium(O) -catalyzed allylic substitution
Vyskocil, Stepan,Smrcina, Martin,Hanus, Vladimir,Polasek, Miroslav,Kocovsky, Pavel
, p. 7738 - 7748 (1998)
CR)-(+)-2-Amino-2′-hydroxy-1,1′-binaphthyl (NOBIN, 5) can be readily converted into a series of novel N,N-disubstituted aminophosphines 9 and 23-25. The N,N-dimethyl derivative (R)-9 (MAP) was prepared via a sequence involving reductive alkylation with CH2O and NaBH4 (5 → 6), Pd-(0)-catalyzed coupling of the corresponding triflate with Ph2P(O)H (7 → 8), and reduction of the resulting phosphine oxide with Cl3SiH (8 → 9). Variation of this scheme was required for the preparation of 23-25 as the phosphinylation failed in the presence of bulky N substituents; the N-protected triflate 17 was first coupled with Ph2P(O)H, and the resulting phosphine oxide 18 was reduced with ClaSiH to give the aminophosphine 19, which was then subjected to reductive alkylation with individual ketones and NaBH4. The new P,N-binaphthyls thus obtained (23-25 and 9) were utilized as chiral ligands in Pd(0)-catalyzed allylic substitution. The enantioselectivites obtained for racemic 1,3-diphenylprop-2-en-l-yl acetate (±)-26 and malonate nucleophiles, which gave (S)-(-)-28, (-)-(+)-29, and (A)-(+)-30 as the respective products (in up to 71-73% ee at room temperature with Cs2CO3 in C2Cl2s and 9 or 23 as a ligand), are interpreted in terms of the chelated transition state 37 and preferential attack at the allylic terminus that is trans with respect to the phosphorus acceptor atom.
Furanoside thioether-phosphinite ligands for Pd-catalyzed asymmetric allylic substitution reactions: Scope and limitations
Diéguez, Montserrat,Pàmies, Oscar,Claver, Carmen
, p. 2257 - 2262 (2006)
A series of readily available thioether-phosphinite ligands has been tested in the Pd-catalyzed allylic substitution reactions of several acyclic and cyclic allylic substrates (S1-S7). This series of ligands have been designed to uncover their important s
Enantioselective allylic substitution, of cinnamyl esters catalyzed by iridium - Chiral aryl phosphite complexs conspicuous change in the mechanistic spectrum by a countercation and solvent
Kinoshita, Naosumi,Marx, Karsten H.,Tanaka, Kiyoshi,Tsubaki, Kazunori,Kawabata, Takeo,Yoshikai, Naohiko,Nakamura, Eiichi,Fuji, Kaoru
, p. 7960 - 7964 (2004)
Indium-catalyzed asymmetric allylic alkylation of monoaryl substrates 4-6 with chiral phosphites 1-3 has been investigated. Although branched isomers were formed with high regioselectivities, the enantioselectivities of these products were remarkably influenced by solvents, countercations, and additives (ZnCl2 and LiCl).
New phosphite-oxazoline ligands for efficient Pd-catalyzed substitution reactions
Pamies, Oscar,Dieguez, Montserrat,Claver, Carmen
, p. 3646 - 3647 (2005)
We have designed and synthesized a new family of readily available highly modular phosphite-oxazoline ligands for the Pd-catalyzed asymmetric allylic substitution reactions. The introduction of a π-acceptor flexible bulky biphenyl phosphite moiety in the ligand design is highly adventitious in the product outcome. Thus, this ligand series affords excellent reaction rates (TOF's up to >2400 mol·(mol·h)-1) and enantioselectivities (ee's up to >99%) and, at the same time, shows a broad scope for different substrate types. Copyright
Very efficient phosphoramidite ligand for asymmetric iridium-catalyzed allylic alkylation
Alexakis, Alexandre,Polet, Damien
, p. 3529 - 3532 (2004)
(Chemical Equation Presented) Linear or branched allylic carbonates or acetates undergo enantioselective iridium-catalyzed allylic substitution with sodium malonate. The reaction is wide in scope and affords the branched product in high yield and with hig
Expanding the scope of the elpaN-type library: Glucose-derived bis(pyridine-2-carboxamide) ligands (elpaN-Py) for molybdenum-catalyzed asymmetric allylic alkylations
Lega, Matteo,Figliolia, Rosario,Moberg, Christina,Ruffo, Francesco
, p. 4061 - 4065 (2013)
The elpaN-Py family of ligands, which represents a subset of the elpaN-type library based on d-glucose, is described. The ligands are structural analogs of the privileged bis(pyridine-2-carboxamides) derived from trans-1,2- diaminocyclohexane, and differ
A highly regioselective salt-free iron-catalyzed allylic alkylation
Plietker, Bernd
, p. 1469 - 1473 (2006)
(Chemical Equation Presented) Ironing out the kinks: A highly regioselective allylic alkylation can be performed in the presence of catalytic amounts of an iron(-II) complex and triphenylphosphane (see scheme; EWG = electron-withdrawing group). Allyl carbonates and pronucleophiles are coupled in high yields with a high regioselectivity comparable only with that obtained with Rh catalysts. The reaction is broadly applicable and does not require external base.
