Day: October 12, 2022

Oonishi, Yoshihiro; Saito, Akira; Sato, Yoshihiro published the artcile< Rhodium(I)-Catalyzed Intermolecular [2+2+2] Cycloaddition of Allenyl Aldehydes with Alkynes and Related Cyclization>, SDS of cas: 139139-86-9, the main research area is polysubstituted dihydropyran enantioselective preparation; internal alkyne allenyl aldehyde rhodium catalyst regioselective cycloaddition; dienyl ketone preparation; terminal alkyne allenyl aldehyde rhodium catalyst cycloaddition.

Rhodium(I)-catalyzed cyclization of allenyl aldehydes with various alkynes was investigated. The intermol. [2+2+2] cycloaddition reaction of allenyl aldehyde with internal alkynes that have both an electron-rich aromatic ring and an electron-withdrawing group at the terminus afforded polysubstituted dihydropyran for e.g., I in good yields with good to high regio- and enantioselectivity. While the reactions of terminal alkynes with allenyl aldehyde gave dienyl ketones instead of [2+2+2] cycloaddition products for e.g., II in good yields.

Asian Journal of Organic Chemistry published new progress about Alkadienones Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, SDS of cas: 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Park, Jihye; Kim, Young Kwang; Kim, Guncheol published the artcile< Stereoselective formal synthesis of (-)-mesembrane via asymmetric allylation and resoluting condensation reactions>, Synthetic Route of 152140-65-3, the main research area is phenylcyclohexanone asym asym allylation; oxocyclohexaneacetamide intramol cyclocondensation resolution; mesembrane stereoselective formal synthesis.

A selective pathway to (-)-mesembrane by a combination of enantioselective allylation and intramol. amide-ketone cyclization was developed.

Bulletin of the Korean Chemical Society published new progress about Allylation, stereoselective. 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, Synthetic Route of 152140-65-3.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Desfeux, Camille; Besnard, Celine; Mazet, Clement published the artcile< [n]Dendralenes as a Platform for Selective Catalysis: Ligand-Controlled Cu-Catalyzed Chemo-, Regio-, and Enantioselective Borylations>, Recommanded Product: (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is phosphanamine copper catalyzed antiMarkovnikov enantioselective borylation substituted dendralene; dendralene preparation enantioselective borylation; crystal structure benzoyl dendralene derivative; mol structure benzoyl dendralene derivative.

The authors report the development of two complementary methods for the Cu-catalyzed anti-Markovnikov borylation of one specific olefin in 2-substituted [n]dendralenes (n = 3-6). The 1st protocol operates with a bisphosphine ligand and occurs with high regio- and chemoselectivity for the terminal double bond, independently of the number of cross-conjugated alkenes. The use of a chiral phosphanamine ligand enables the highly chemo-, regio-, and enantioselective borylation of the alkene cross-conjugated with the terminal olefin in [n]dendralenes.

Organic Letters published new progress about Borylation (anti-Markovnikov enantioselective). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Recommanded Product: (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Lipshutz, Bruce H.; Amorelli, Benjamin; Unger, John B. published the artcile< CuH-Catalyzed Enantioselective Intramolecular Reductive Aldol Reactions Generating Three New Contiguous Asymmetric Stereocenters>, Recommanded Product: (2S)-1-[(1S)-1-[Bis(1,1-dimethylethyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene, the main research area is unsaturated ketone copper enantioselective intramol reductive aldol chiral phosphine; cycloalkanol stereoselective preparation; enantioselective intramol reductive aldol catalyst copper chiral phosphine.

Treatment of β,β-disubstituted-α,β-unsaturated ketones, e.g., I, bearing a ketone residue with in situ generated, catalytic CuH ligated by a nonracemic ligand leads to cycloalkanols, e.g., II, with three newly created adjacent chiral centers. Excellent de’s and ee’s are obtained for several examples studied.

Journal of the American Chemical Society published new progress about Aldol condensation catalysts, stereoselective (intramol.). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Recommanded Product: (2S)-1-[(1S)-1-[Bis(1,1-dimethylethyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Nishida, Goushi; Noguchi, Keiichi; Hirano, Masao; Tanaka, Ken published the artcile< Enantioselective synthesis of P-stereogenic alkynylphosphine oxides by Rh-catalyzed [2+2+2] cycloaddition>, HPLC of Formula: 139139-86-9, the main research area is alkynyl phosphine oxide preparation stereoselective structure; cycloaddition dialkynyl phosphine oxide diyne rhodium binap complex catalyst; crystal mol structure stereogenic phosphorus alkynyl phosphine oxide preparation.

An enantioselective synthesis of P-stereogenic alkynylphosphine oxides through a cationic rhodium(l)/modified-binap complex catalyzed [2+2+2] cycloaddition of sym. dialkynylphosphine oxides with 1,6-diynes was developed (binap = 2,2′-bis(diphenylphosphinyl)-1,1′-binaphthyl, Z = CH2, O, or N-sulfonamide). Furthermore, this method permits the synthesis of a C2-sym. P-stereogenic bis(alkynylphosphine oxide). A crystal structure of one product was determined along with the absolute configuration of the phosphorus center.

Angewandte Chemie, International Edition published new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent) (1,6-diynes). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, HPLC of Formula: 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Fernandez, Marti; Parera, Magda; Parella, Teodor; Lledo, Agusti; Le Bras, Jean; Muzart, Jacques; Pla-Quintana, Anna; Roglans, Anna published the artcile< Rhodium-Catalyzed [2+2+2] Cycloadditions of Diynes with Morita-Baylis-Hillman Adducts: A Stereoselective Entry to Densely Functionalized Cyclohexadiene Scaffolds>, Application of C44H40P2, the main research area is cyclohexadiene scaffold enantioselective preparation; diyne Morita Baylis Hillman adduct enantioselective cycloaddition rhodium catalyst.

A rhodium-catalyzed asym. synthesis of 5,5-disubstituted cyclohexa-1,3-dienes has been achieved by [2+2+2] cycloaddition reactions between diynes and Morita-Baylis-Hillman (M-B-H) adducts as unsaturated substrates. Products containing two adjacent chiral centers (quaternary and tertiary, resp.) were obtained with complete diastereoselectivity and high enantioselectivity (84-97%) through a kinetic resolution of the M-B-H adduct. Furthermore, these highly substituted cyclohexadienes reacted with dienophiles to afford the corresponding Diels-Alder cycloadducts in good yields.

Advanced Synthesis & Catalysis published new progress about Alkadiynes Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Application of C44H40P2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Bates, Roderick W.; Li, Lu; Palani, Kalpana; Phetsang, Wanida; Loh, Joanna Kejun published the artcile< Synthesis of the Tetrahydropyran Fragment of Bistramide D>, SDS of cas: 152140-65-3, the main research area is bistramide D tetrahydropyran fragment enantioselective preparation.

A synthesis of the tetrahydropyran (THP) moiety of bistramide D has been completed by using cross-metathesis and kinetically controlled intramol. oxa-Michael addition to form the ring with excellent trans selectivity. The C9 Me substituent was introduced by using an unsaturated sulfone building block, which can be most effectively prepared through a combination of diastereoselective allylation and alkene isomerisation. The effect of this Me group on subsequent cross-metathesis reactions can be mitigated by careful choice of reaction conditions.

Asian Journal of Organic Chemistry published new progress about Cross-metathesis. 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, SDS of cas: 152140-65-3.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Wang, Duo-Sheng; Tang, Jie; Zhou, Yong-Gui; Chen, Mu-Wang; Yu, Chang-Bin; Duan, Ying; Jiang, Guo-Fang published the artcile< Dehydration triggered asymmetric hydrogenation of 3-(α-hydroxyalkyl)indoles>, Related Products of 139139-86-9, the main research area is stereoselective hydrogenation hydroxyalkyl indole reactant alkylindoline preparation; palladium catalyzed asym hydrogenation hydroxyalkyl indole reactant; hydroxyalkyl indole preparation formylation Grignard addition indole reactant.

Highly enantioselective hydrogenation of 3-(α-hydroxyalkyl)indoles promoted by a Bronsted acid for dehydration to form a vinylogous iminium intermediate in situ was developed with Pd(OCOCF3)2/(R)-H8-BINAP as catalyst with up to 97% ee. This methodol. provides an efficient and rapid access to chiral 2,3-disubstituted indolines, e.g. I (R1 = 5-F, 7-Me, R2 = H; R1 = H, R2 = 2-Me, 4-MeO, 4-F).

Chemical Science published new progress about Diastereoselective synthesis. 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Related Products of 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Rasson, Corentin; Riant, Olivier published the artcile< Copper(I) Diphosphine Bifluoride Complexes as Efficient Preactivated Catalysts for Nucleophilic Addition on Unsaturated Functional Groups>, Category: chiral-phosphine-ligands, the main research area is copper diphosphine bifluoride complex catalyst preparation nucleophilic addition; nucleophilic copper addition pronucleophile aldehyde ketone.

Herein we report the synthesis of a family of copper(I) diphosphine bifluoride complexes, their characterization, and their use as efficient preactivated catalysts for nucleophilic copper addition of pronucleophiles on unsaturations. Their use as mechanistic probes is also highlighted by the identification of two copper deuterides.

Organic Process Research & Development published new progress about Allylation catalysts, stereoselective. 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Category: chiral-phosphine-ligands.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Roy, Amy H.; Hartwig, John F. published the artcile< Oxidative Addition of Aryl Tosylates to Palladium(0) and Coupling of Unactivated Aryl Tosylates at Room Temperature>, Application of C32H40FeP2, the main research area is palladium oxidative addition phenyl tosylate mechanism kinetics; crystal structure palladium phenyl bromo ferrocene diphosphine chelate preparation; mol structure palladium phenyl bromo ferrocene diphosphine chelate; aryl tosylate unactivated cross coupling Grignard palladium catalyst; biaryl unsym preparation.

Aryl tosylates are attractive substrates for Pd-catalyzed cross-coupling reactions, but they are much less reactive than the more commonly used aryl triflates. The authors report the oxidative addition of aryl tosylates to Pd(PPF-t-Bu)[P(o-tolyl)3] [PPF-t-Bu = 1-diphenylphosphino-2-(di-tert-butylphosphinoethyl)ferrocene] and to Pd(CyPF-t-Bu)[P(o-tolyl)3] [CyPF-t-Bu = 1-dicyclohexylphosphino-2-(di-tert-butylphosphinoethyl)ferrocene] at room temperature to produce the corresponding Pd(II) aryl tosylate complexes (shown as I; R = Ph, X = OTs 3; R = cyclohexyl, X = OTs 4). In the presence of added bromide ions, arylpalladium(II) bromide complexes I (R = Ph, X = Br 5 ; R = cyclohexyl, X = Br 6) were formed. The structures of 5 and 6 were determined by x-ray crystallog. The rate of oxidative addition was accelerated by addition of either coordinating or weakly coordinating anions, and the reactions were faster in more polar solvents. The mild conditions for oxidative addition allowed the development of Pd-catalyzed Kumada couplings and amination reactions of unactivated aryl tosylates at room temperature The catalysts for these mild couplings of aryl tosylates were generated from Pd precursors and the sterically hindered Josiphos-type ligands that induced oxidative addition of aryl tosylates to Pd(0) at room temperature Thus, coupling reaction of XC6H4OTs (X = 2- and 4-MeO, 4-CF3, 4-Me) or of mesityl tosylate or of 1-naphthyl tosylate with aryl Grignard reagents ArMgBr (Ar = 4-tolyl, 4-FC6H4, 4-MeOC6H4) in PhMe in presence of 0.1-1.0 mol % Pd(dba)2 and PPF-t-Bu at either 25° or 80° gave the corresponding biaryls in 40-86% yields.

Journal of the American Chemical Society published new progress about Amination catalysts. 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Application of C32H40FeP2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate