Tag: M.W=600-700

Hato, Yoshio; Oonishi, Yoshihiro; Yamamoto, Yasunori; Nakajima, Kiyohiko; Sato, Yoshihiro published the artcile< Stereoselective Construction of Spiro-Fused Tricyclic Frameworks by Sequential Reaction of Enynes, Imines, and Diazoalkenes with Rh(I) and Rh(II) Catalysts>, Safety of (S)-(-)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is stereoselective spiro fused tricyclic compound; rhodium catalyst imine tethered enyne reaction diazoalkene.

Stereoselective construction of spiro-fused tricyclic compounds from enynes having a tethered imine with diazoalkenes was achieved by Rh(I)- and Rh(II)-catalyzed sequential reactions. This method consists of three reactions, i.e., Rh(I)-catalyzed cyclization of enynes with a tethered imine, Rh(II)-catalyzed cyclopropanation with diazoalkenes, and Cope rearrangement. Notably, the sequential reactions can be operated in one pot, in which Rh(I) and Rh(II) catalysts work in relay without any serious catalyst deactivation to afford the spirocycles in a stereoselective manner.

Journal of Organic Chemistrypublished new progress about Alkenynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Safety of (S)-(-)-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

Tanaka, Ken; Nishida, Goushi; Sagae, Hiromi; Hirano, Masao published the artcile< Enantioselective synthesis of C2-symmetric dimethyl cyclohexadienedicarboxylates through cationic rhodium(I)/modified-BINAP-catalyzed [2+2+2] cycloadditions>, Application of C44H40P2, the main research area is enediyne enantioselective intramol cycloaddition rhodium BINAP catalyst; diyne fumarate enantioselective cycloaddition rhodium BINAP catalyst; tricyclic cyclohexadienedicarboxylate asym synthesis; bicyclic cyclohexadienedicarboxylate asym synthesis.

A cationic rhodium(I)/(S)-Tol-BINAP complex was employed to catalyze an enantioselective intramol. [2+2+2] cycloaddition of a trans enediyne leading to a C2-sym. tricyclic di-Me cyclohexadienedicarboxylate in 95% yield with 59% ee. A cationic rhodium(I)/(R)-H8-BINAP complex was employed to catalyze an intermol. [2+2+2] cycloaddition of 1,6-diynes with di-Me fumarate leading to C2-sym. bicyclic di-Me cyclohexadienedicarboxylates in 35-96% yields with 82-98% ee.

Synlettpublished new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent). 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

Chang, Xin; Ma, Pei-Long; Chen, Hong-Chao; Li, Chuan-Ying; Wang, Peng published the artcile< Asymmetric Synthesis and Application of Chiral Spirosilabiindanes>, Related Products of 139139-93-8, the main research area is alkenyldihydrosilane preparation rhodium catalyzed asym double hydrosilation spirocyclization; spirosilabiindane chiral preparation reaction aminophosphine; phosphoramidite spirosilabiindane chiral preparation catalyst ligand asym hydrogenation carboamination; crystal structure chiral spirosilabiindane diol derivative phosphoramidite; mol structure chiral spirosilabiindane diol derivative phosphoramidite; asymmetric catalysis; ligand design; silanes; spirocompounds; synthetic methods.

Reported here is the development of a class of chiral spirosilabiindane scaffolds by Rh-catalyzed asym. double hydrosilation, for the 1st time. Enantiopure SPSiOL (spirosilabiindane diol), a new type of chiral building block for the preparation of various chiral ligands and catalysts, was readily prepared on >10 g scale using this protocol. The potential of this new spirosilabiindane scaffold in asym. catalysis was preliminarily demonstrated by development of the corresponding monodentate phosphoramidite ligands (SPSiPhos), which were used in both a Rh-catalyzed hydrogenation and a Pd-catalyzed intramol. carboamination.

Angewandte Chemie, International Editionpublished new progress about Alkenes Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation) (bis(alkenyl)dihydrosilanes). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Related Products of 139139-93-8.

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

Felix, Ryan J.; Weber, Dieter; Gutierrez, Osvaldo; Tantillo, Dean J.; Gagne, Michel R. published the artcile< A gold-catalysed enantioselective Cope rearrangement of achiral 1,5-dienes>, HPLC of Formula: 325168-88-5, the main research area is gold catalysis enantioselective cope rearrangement achiral dienes.

Since the discovery of the Cope rearrangement in the 1940s, no asym. variant of the rearrangement of achiral 1,5-dienes has emerged, despite the successes that have been achieved with its heteroatom variants (Claisen, aza-Cope, and so on). This article reports the first example of an enantioselective Cope reaction that starts from an achiral diene. The new gold(I) catalyst derived from double Cl–abstraction of ((S)-3,5-xylyl-PHANEPHOS(AuCl)2), has been developed for the sigmatropic rearrangement of alkenyl-methylenecyclopropanes. The reaction proceeds at low temperature and the synthetically useful vinylcyclopropane products are obtained in high yield and enantioselectivity. D. functional theory calculations predict that: (1) the reaction proceeds via a cyclic carbenium ion intermediate, (2) the relief of strain in the methylenecyclopropane moiety provides the thermodn. driving force for the rearrangement and (3) metal complexation of the transition-state structure lowers the rearrangement barriers.

Nature Chemistrypublished new progress about [3,3]-Sigmatropic rearrangement. 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, HPLC of Formula: 325168-88-5.

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

Tanaka, Ken; Takahashi, Maho; Imase, Hidetomo; Osaka, Takuya; Noguchi, Keiichi; Hirano, Masao published the artcile< Enantioselective synthesis of α,α-disubstituted α-amino acids by Rh-catalyzed [2+2+2] cycloaddition of 1,6-diynes with protected dehydroamino acid>, Recommanded Product: (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is enantioselective synthesis amino acid rhodium BINAP catalyst cycloaddition diyne; dehydroamino acid cycloaddition diyne catalyst rhodium BINAP.

We have determined that a cationic rhodium(I)/BINAP complex catalyzes a [2+2+2] cycloaddition of 1,6-diynes with protected dehydroamino acids, leading to protected α-amino acids bearing a quaternary carbon center in high yield with high enantioselectivity. Thus, aminoisoindolecarboxylate I (Ts = tosyl) was obtained in 96% yield and 97 ee by cycloaddition reaction of TsN(CH2CCMe)2 with AcNHC(:CH2)CO2Me using Rh(cod)2BF4/(R)-BINAP.

Tetrahedronpublished new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent). 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

Senda, Taichi; Ogasawara, Masamichi; Hayashi, Tamio published the artcile< Rhodium-Catalyzed Asymmetric 1,4-Addition of Organoboron Reagents to 5,6-Dihydro-2(1H)-pyridinones. Asymmetric Synthesis of 4-Aryl-2-piperidinones>, Formula: C44H40P2, the main research area is asym synthesis arylpiperidinone; stereoselective addition organoboron pyridinone; paroxetine intermediate stereoselective preparation.

Catalytic asym. synthesis of 4-aryl-2-piperidinones was realized by asym. 1,4-addition of arylboron reagents to 5,6-dihydro-2(1H)-pyridinones in the presence of a chiral bisphosphine-rhodium catalyst. In the reaction introducing the 4-fluorophenyl group, the use of 4-fluorophenylboroxine and 1 equiv (to boron) of water at 40°C gave the highest yield of the arylation product with high enantioselectivity (98% ee). The (R)-4-(4-fluorophenyl)-2-piperidinone obtained is a key intermediate for the synthesis of (-)-Paroxetine.

Journal of Organic Chemistrypublished new progress about Addition reaction catalysts, stereoselective. 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Formula: 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

Brusoe, Andrew T.; Alexanian, Erik J. published the artcile< Rhodium(I)-Catalyzed Ene-Allene-Allene [2+2+2] Cycloadditions: Stereoselective Synthesis of Complex trans-Fused Carbocycles>, COA of Formula: C44H40P2, the main research area is eneallene allene rhodium catalyzed cycloaddition; hydrindane decalin stereoselective preparation four contiguous stereocenters; fused carbocycle stereoselective preparation.

The rhodium-catalyzed [2+2+2] cycloaddition of ene-allenes with allenes was utilized for the construction of a variety of trans-fused hydrindanes and decalins in a highly convergent manner, with three σ bonds, two rings, and up to four contiguous stereocenters generated in a regio- and stereoselective fashion.

Angewandte Chemie, International Editionpublished new progress about Allenes 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, COA of Formula: 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

Yasui, Takeshi; Nakazato, Yuya; Kurisaki, Koutarou; Yamamoto, Yoshihiko published the artcile< Enantioselective Construction of 5-6-5 Tricyclic Lactone Framework Bearing a Quaternary Bridgehead Carbon via Rh-Catalyzed Asymmetric [2+2+2] Cycloaddition of Enediynes>, Recommanded Product: (S)-(-)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is tricyclic cyclohexadiene lactone preparation enantioselective; enediyne cycloaddition rhodium catalyst.

Herein, a Rh-catalyzed asym. [2+2+2] cycloaddition of ene-yne-yne enediynes to generate enantio-enriched tricyclic cyclohexadienes bearing a quaternary bridgehead carbon is reported. The Rh-Phanephos complex is an appropriate catalyst for the cycloaddition of enediynes bearing an unsubstituted propiolate terminus, whereas Rh-biaryl bisphosphine catalysts, which have been widely used for asym. cycloadditions of alkynes and alkenes, are not applicable for the reaction of such enediynes. Several control experiments suggest that the reaction using the Rh-Phanephos complex exclusively proceeds via a rhodacyclopentadiene intermediate, unlike when using a Rh-biaryl bisphosphine complex that can form a rhodacyclopentadiene intermediate as well as a rhodacyclopentene intermediate in a substrate-dependent manner.

Advanced Synthesis & Catalysispublished new progress about [2+2+2] Cycloaddition reaction (stereoselective). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Recommanded Product: (S)-(-)-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

Tsuchikama, Kyoji; Yoshinami, Yusuke; Shibata, Takanori published the artcile< Rhodium-complex-catalyzed [2+2+2] cycloaddition of diynes and carbonyl compounds>, Synthetic Route of 139139-93-8, the main research area is diyne carbonyl stereoselective cycloaddition rhodium BINAP catalyst; hydropyran stereoselective preparation electrocyclic ring opening; cyclopentene stereoselective preparation; hydropyrrole stereoselective preparation; hydrofuran stereoselective preparation.

A Rh-BINAP complex was used to catalyze the hetero-[2+2+2] cycloaddition of sym. 1,6-diynes and carbonyl moiety of keto esters, a diketone, and an aldehyde to give bicyclic α-pyrans, which were readily transformed into monocyclic compounds via the following electrocyclic ring opening. In the reaction of an unsym. 1,6-diyne and a 1,7-diyne, α-pyrans with a quaternary carbon stereocenter were obtained in moderate to excellent ee using a chiral rhodium catalyst.

Synlettpublished new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Synthetic Route of 139139-93-8.

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

Mullen, Charles A.; Campbell, Alison N.; Gagne, Michel R. published the artcile< Asymmetric oxidative cation/olefin cyclization of polyenes: evidence for reversible cascade cyclization>, Quality Control of 325168-88-5, the main research area is polyenol xylylphanephos platinum silver enantioselectively diastereoselectively regioselectively oxidative cyclization; fused oxygen containing heterocycle stereoselective preparation reaction determining step.

Activation of [(xylyl-phanephos)PtCl2] by silver generates an electrophilic catalyst that can enantioselectively, diastereoselectively, and regioselectively promote the stereospecific oxidative cyclization of polyene-ols. Mechanistic experiments indicate that the stereochem.-determining step is not the initial cyclization step, but rather a subsequent step in the reaction.

Angewandte Chemie, International Editionpublished new progress about Alkenyl alcohols Role: RCT (Reactant), RACT (Reactant or Reagent). 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Quality Control of 325168-88-5.

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