Tag: 354.5256

Phosphonites Based on the Paracyclophane Backbone: New Ligands for Highly Selective Rhodium-Catalyzed Asymmetric Hydrogenation was written by Zanotti-Gerosa, Antonio;Malan, Christophe;Herzberg, Daniela. And the article was included in Organic Letters in 2001.Safety of (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol This article mentions the following:

The synthesis of new phosphonites with a chiral paracyclophane backbone is described. The Rh complexes derived from the phosphonites (e.g. I) bearing biphenoxy and binaphthoxy substituents are highly active and highly selective catalysts for the asym. hydrogenation of dehydroamino acids and esters. For example, >99% N-acetylalanine Me ester with 99 %ee was obtained in 1/2 h using the Rh complex of I. In the experiment, the researchers used many compounds, for example, (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3Safety of (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol).

(S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3) belongs to copper catalysts. Copper catalyst has received great attention owing to the low toxicity and low cost. Copper nanoparticles can also catalyze the coupling reaction of nitrogen-containing nucleophiles, phenols, thiols, xanthogenates, selenium ruthenium nucleophiles and the like.Safety of (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol

Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”

Synthesis of Tungsten Oxo Alkylidene Biphenolate Complexes and Ring-Opening Metathesis Polymerization of Norbornenes and Norbornadienes was written by Yan, Tao;VenkatRamani, Sudarsan;Schrock, Richard R.;Muller, Peter. And the article was included in Organometallics in 2019.Safety of (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol This article mentions the following:

We have synthesized and characterized tungsten oxo alkylidene biphenolate complexes with the formulas W(O)(CHR)(rac-biphenolate)(PPhMe₂) and (R,S)-[W(μ-O)(CHR)(biphenolate)]₂ (R = CMe₂Ph; biphenolate = L1 or L2 in the text). They behave as initiators for the stereoselective (cis,isotactic) polymerization of 2,3-dicarbomethoxy-5-norbornadiene and eight enantiomerically pure 5-substituted norbornenes with a cis,isotactic precision of 95-98% in most cases. The active initiators are 14e W(O)(CHR)(biphenolate) complexes, which are formed through either dissociation of PPhMe₂ from the phosphine adducts or scission of the heterochiral dimer. Addition of B(C₆F₅)₃ (one per W) to (R,S)-[W(μ-O)(CHR)(L1)]₂ led to formation of what we propose to be monomeric W[OB(C₆F₅)₃](CHR)(L1) in equilibrium with B(C₆F₅)₃ and (R,S)-[W(μ-O)(CHR)(L1)]₂. This mixture decomposed over a period of 1-2 h, was much slower to initiate polymerization than (R,S)-[W(μ-O)(CHR)(L1)]₂, and was much less stereoselective. Polymerization of five of the monomers with the imido alkyidene initiator, W(N-2,6-Me₂C₆H₃)(CHCMe₂Ph)(rac-L1), gave virtually identical results compared to the results obtained with oxo complexes. In the experiment, the researchers used many compounds, for example, (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3Safety of (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol).

(S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3) belongs to copper catalysts. Copper catalyst has received great attention owing to the low toxicity and low cost. Copper nanoparticles can also catalyze the coupling reaction of phenols, thiols, xanthogenates, nitrogen-containing nucleophiles, selenium ruthenium nucleophiles and the like.Safety of (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol

Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”

Phospholane-Phosphite Ligands for Rh Catalyzed Enantioselective Conjugate Addition: Unusually Reactive Catalysts for Challenging Couplings was written by Gilbert, Sophie H.;Fuentes, Jose A.;Cordes, David B.;Slawin, Alexandra M. Z.;Clarke, Matthew L.. And the article was included in European Journal of Organic Chemistry in 2020.Electric Literature of C24H34O2 This article mentions the following:

The use of Rh catalysts derived from a phospholane-phosphite ligand were found to be more productive than the classic rhodium/BINAP system in enantioselective conjugate additions These catalysts enable the use of lower amounts of aryl boronic acid in an asym. arylation reaction that required an impractical excess of nucleophile. This catalyst was also found to enable the coupling of a poorly reactive Michael acceptor, N-CBz-2-3-dehydro-4-piperidone, or the coupling of poorly reactive 2-furyl boronic acids at ambient or near temperatures In the experiment, the researchers used many compounds, for example, (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3Electric Literature of C24H34O2).

(S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3) belongs to copper catalysts. The evolution of transition metal catalysts has attained a stage of civilization that authorizes for an extensive scope of chemical bonds formation partners to be combined efficiently. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. Electric Literature of C24H34O2

Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”

Synthesis and Application of a New Bisphosphite Ligand Collection for Asymmetric Hydroformylation of Allyl Cyanide was written by Cobley, Christopher J.;Gardner, Kelli;Klosin, Jerzy;Praquin, Celine;Hill, Catherine;Whiteker, Gregory T.;Zanotti-Gerosa, Antonio;Petersen, Jeffrey L.;Abboud, Khalil A.. And the article was included in Journal of Organic Chemistry in 2004.Synthetic Route of C24H34O2 This article mentions the following:

A series of mono- and bidentate phosphites was prepared with (S)-5,5′,6,6′-tetramethyl-3,3′-di-tert-butyl-1,1′-biphenyl-2,2′-dioxy [(S)-BIPHEN] as a chiral auxiliary and screened in the asym. hydroformylation of butenenitrile. These hydroformylation results were compared with those of two existing chiral ligands, Chiraphite and BINAPHOS, whose utility in asym. hydroformylation has been previously demonstrated. One bis(phosphite) with a 2,2′-biphenol bridge was found to be the best overall ligand for asym. hydroformylation of allyl cyanide with up to 80% ee and regioselectivities (branch-to-linear ratio, b/l) of 20 with turnover frequency of 625 [h^-1] at 35 °C. BINAPHOS gave enantioselectivities up to 77% ee when the reaction was conducted in either acetone or neat but with poor regioselectivity (b/l 2.8) and activities 7 times lower than that of (S,S)-Kelliphite [(S,S)-I]. The product of butenenitrile hydroformylation using (11aR,11’aR)-[[[1,1′-biphenyl]diyl]bis(oxy)]bis[dibenzo[d,f][1,3,2]dioxaphosphepin], i.e. (R,R)-I [(R,R)-Kelliphite] was subsequently transformed into (R)-4-amino-2-methyl-1-butanol, a useful chiral building block. Single-crystal X-ray structures of (S,S)-I and its rhodium complex were determined In the experiment, the researchers used many compounds, for example, (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3Synthetic Route of C24H34O2).

(S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3) belongs to copper catalysts. The transition metal-catalyzed chemical transformation of organic electrophiles and organometallic reagents has turned up as an exceedingly robust synthetic tool. Copper nanoparticles can also catalyze the coupling reaction of nitrogen-containing nucleophiles, phenols, thiols, xanthogenates, selenium ruthenium nucleophiles and the like.Synthetic Route of C24H34O2

Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”

Asymmetric Hydroformylation of Heterocyclic Olefins Mediated by Supramolecularly Regulated Rhodium-Bisphosphite Complexes was written by Rovira, Laura;Vaquero, Monica;Vidal-Ferran, Anton. And the article was included in Journal of Organic Chemistry in 2015.Synthetic Route of C24H34O2 This article mentions the following:

Rhodium complexes derived from conformationally transformable α,ω-bisphosphite ligands combined with a suitable alkali metal BArF salt as a regulation agent (RA) provide high regio- and enantioselectivities in the asym. hydroformylation (AHF) of three heterocyclic olefins. The outcome of the AHF could be exquisitely regulated by choosing the appropriate RA with an increase in the ee, the reversal of the regioselectivity, or the complete suppression of one byproduct. In the experiment, the researchers used many compounds, for example, (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3Synthetic Route of C24H34O2).

(S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3) belongs to copper catalysts. The applications of Copper-based nanoparticles have received great attention due to low toxicity and inexpensive, earth-abundant. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. Synthetic Route of C24H34O2

Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”

Organomagnesiate-Promoted Enantioselective Cascade Process: Straightforward Access to Chiral 3-Substituted Isobenzofuranones was written by Touchet, Sabrina;Kommidi, Sai Shradha Reddy;Gros, Philippe C.. And the article was included in ChemistrySelect in 2018.Computed Properties of C24H34O2 This article mentions the following:

The bimetallic organomagnesiate complex (S)-(BIPHEN)BuMgLi was reported as a dual efficient halogen-metal exchange and chirality transfer agent in the reaction of ethyl-2-iodobenzoate with aldehydes leading to the formation of various chiral 3-substituted isobenzofuranones in good yields and enantiomeric ratios. In the experiment, the researchers used many compounds, for example, (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3Computed Properties of C24H34O2).

(S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3) belongs to copper catalysts. The applications of Copper-based nanoparticles have received great attention due to the earth-abundant, low toxicity and inexpensive. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. Computed Properties of C24H34O2

Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”

High enantioselectivity is induced by a single monodentate phosphoramidite ligand in iridium-catalyzed asymmetric hydrogenation was written by Giacomina, Francesca;Meetsma, Auke;Panella, Lavinia;Lefort, Laurent;de Vries, Andre H. M.;de Vries, Johannes G.. And the article was included in Angewandte Chemie, International Edition in 2007.Computed Properties of C24H34O2 This article mentions the following:

Stripping a catalyst down to its bare essentials makes a neutral iridium complex, containing only one monodentate phosphoramidite ligand, an efficient catalyst for the enantioselective hydrogenation of α-dehydroamino acids. For example, neutral iridium chiral catalyst [Ir(COD)(L)Cl], where L = (S)-(3,3′-di-tert-butyl-5,5′,6,6′-tetramethyl-1,1′-biphenyl-2,2′-diyl)-N,N-dimethylphosphoramidite (I), is an effective catalyst for the asym. hydrogenation of PhCH:C(NHCOMe)CO₂Me to N-acetylphenylalaninate Me ester. In the experiment, the researchers used many compounds, for example, (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3Computed Properties of C24H34O2).

(S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3) belongs to copper catalysts. Copper catalyst has received great attention owing to the low toxicity and low cost. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. Computed Properties of C24H34O2

Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”

Electronic Differences between Coordinating Functionalities of Chiral Phosphine-Phosphites and Effects in Catalytic Enantioselective Hydrogenation was written by Suarez, Andres;Mendez-Rojas, Miguel A.;Pizzano, Antonio. And the article was included in Organometallics in 2002.HPLC of Formula: 205927-03-3 This article mentions the following:

A convenient synthesis of new chiral phosphine-phosphites (P-OP) was described. The versatility of the synthetic protocol developed gave ligands with different phosphine fragments and the choice of the stereogenic element location. Analyses of the values of ¹J_PSe of the corresponding diselenides are in accord with the expected lower σ-donor ability of the phosphite fragment, with respect to the phosphine group, and with an increase of phosphine basicity after substitution of Ph substituents by Me groups. Inspection of υ(CO) values on complexes RhCl(CO)(P-OP) demonstrated a variable π-acceptor ability of the phosphite group, compensating for the change of basicity of the phosphine functionality, as well as having a rather reduced electron d. at the metal center compared with diphosphine analogs. The distinct nature of the P functionalities also was evidenced in Rh-catalyzed enantioselective hydrogenation of Me Z-α-acetamidocinnamate (MAC). Thus, the coordination mode of the substrate is governed by the chiral ligand, directing the olefinic bond to a cis position with respect to the phosphite group, as demonstrated by NMR studies performed with [Rh(P-OP)(MAC)]⁺ complexes. In consequence, the phosphite group has a greater impact on the enantioselectivity of the product. However, the optical purity of the process also depends on the nature of the phosphine group, and hence, an appropriate election of both P functionalities is required for the attainment of excellent enantioselectivities (99% ee). In the experiment, the researchers used many compounds, for example, (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3HPLC of Formula: 205927-03-3).

(S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol (cas: 205927-03-3) belongs to copper catalysts. Transition metal-catalyzed chemical transformation of organic electrophiles and organometallic reagents belong to the most important cross-coupling reaction in organic synthesis. These ligands enable the reaction promoted in mild condition. The reaction scope has also been greatly expanded, rendering this copper-based cross-coupling attractive for both academia and industry. HPLC of Formula: 205927-03-3

Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”