Tag: 354.5256

Molybdenum alkylidyne complexes that contain a 3,3′-di-t-butyl-5,5′,6,6′-tetramethyl-1,1′-biphenyl-2,2′-diolate ([Biphen]^2-) ligand was written by Schrock, Richard R.;Jamieson, Jennifer Y.;Araujo, James P.;Bonitatebus, Peter J.;Sinha, Amritanshu;Lopez, L. Pia H.. And the article was included in Journal of Organometallic Chemistry in 2003.Application In Synthesis of (S)-3,3′-Di-tert-butyl-5,5′,6,6′-tetramethylbiphenyl-2,2′-diol This article mentions the following:

The reaction between K₂[Biphen] ([Biphen]^2- = 3,3′-di-tert-butyl-5,5′,6,6′-tetramethyl-1,1′-biphenyl-2,2′-diolate) and Mo(NAr_Cl)(CH-t-Bu)(OTf)₂(dme) (Ar_Cl = 2,6-Cl₂C₆H₃) in the presence of ten equiv NEt₃ gave Mo(NHAr_Cl)(C-t-Bu)[Biphen] (4a) in 40-50% yield. Addition of K₂[S-Biphen] to Mo(NAr_Cl)(CHCMe₂Ph)(OTf)₂(THF) in THF gave Mo(NHAr_Cl)(CCMe₂Ph)[S-Biphen] (4b) in ∼40% yield. An x-ray crystal study of 4b confirmed the proposed structure and also revealed that one ortho chloride approaches within 2.93 Å of the metal approx. trans to the alkylidyne ligand. Addition of one equiv H₂[Biphen] to Mo(CCH₂SiMe₃)[N(i-Pr)Ar”]₃ (Ar” = 3,5-dimethylphenyl) produced Mo(CCH₂SiMe₃)[Biphen][N(i-Pr)Ar”] in situ, which when treated with one equiv 1-adamantanol gave a mixture of Mo(CCH₂SiMe₃)[Biphen](OAd) (9) and three equiv HN(i-Pr)Ar”, from which 9 could be isolated as a beige powder in 46% yield. An x-ray study of 9 confirmed that it is a pseudotetrahedral species in which the MoC bond length is 1.707(15) Å and the MoC-C angle is 168.3(11)°. Addition of ten equiv 2-butyne or 3-hexyne to a pale yellow solution of 9 produced the molybdacyclobutadiene complexes Mo(C₃R₃)[Biphen](OAd) (R = Me or Et; 10a and 10b, resp.) in high yield. Both 10a and 10b decompose slowly in solution, even in the presence of added alkyne. An x-ray structure of the decomposition product of 10a revealed it to have the stoichiometry of 10a plus one addnl. equiv of 2-butyne. The most unusual feature of the structure of this alkyne complex is a fusion of the C₃Me₃ portion of the metallacyclobutadiene ring to carbons in position 5 and 6 in the [Biphen]^2- backbone to create a σ allyl linkage. These results suggest that Mo biphenolate alkylidyne complexes are not likely to be stable under conditions where alkynes are metathesized. 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: 205927-03-3Application In Synthesis 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. 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. 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. Application In Synthesis 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”

An asymmetric hydroformylation catalyst that delivers branched aldehydes from alkyl alkenes was written by Noonan, Gary M.;Fuentes, Jose A.;Cobley, Christopher J.;Clarke, Matthew L.. And the article was included in Angewandte Chemie, International Edition in 2012.SDS of cas: 205927-03-3 This article mentions the following:

A rhodium-catalyzed asym. hydroformylation of terminal alkenes in presence of a phosphine-phosphite chiral ligand is described. Branched chiral aldehydes were obtained in good to excellent enantioselectivities using this strategy. 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: 205927-03-3SDS of cas: 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. The transition metal-catalyzed chemical transformation of organic electrophiles and organometallic reagents has turned up as an exceedingly robust synthetic tool. The copper-mediated C-C, C-O, C-N, and C-S bond formation is a part of one oldest reaction, emphasizing the Ullmann cross-coupling reaction.SDS of cas: 205927-03-3

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

Synthesis of Molybdenum Imido Alkylidene Complexes That Contain 3,3′-Dialkyl-5,5′,6,6′-tetramethyl-1,1′-biphenyl-2,2′-diolates (Alkyl = t-Bu, Adamantyl). Catalysts for Enantioselective Olefin Metathesis Reactions was written by Alexander, John B.;Schrock, Richard R.;Davis, William M.;Hultzsch, Kai C.;Hoveyda, Amir H.;Houser, Jeffrey H.. And the article was included in Organometallics in 2000.Category: copper-catalyst This article mentions the following:

Two 3,3′-dialkyl-5,5′,6,6′-tetramethyl-1,1′-biphenyl-2,2′-diols (alkyl = t-Bu, 1-adamantyl) were prepared in two steps and resolved as the menthol phosphate derivative Addition of the dipotassium salt of each biphenolate to various Mo(N-Aryl)(CHR)(OTf)₂(DME) complexes produced racemic and enantiopure compounds Mo(N-aryl)(CHR)(biphenolate). X-ray crystallog. studies of syn-Mo(N-2,6-i-Pr₂C₆H₃)(CHCMe₂Ph)[(S)-Biphen] and syn-Mo(N-2-CF₃C₆H₄)(CHCMe₃)[(S)-Biad](pyridine) proved the absolute stereochem. of the biphenolate ligands. Neophylidene and neopentylidene complexes have predominantly the syn conformation in solution The [syn]/[anti] equilibrium constant for Mo(N-Aryl)(CHR)[Biphen] complexes increased in magnitude with decreasing size of the arylimido ligand, and decreased upon reducing the steric bulk of the alkylidene substituent. The rates of exchange of syn and anti isomers, as determined by single-parameter line shape anal. and by spin saturation transfer, are on the order of ∼1 s^-1 at 22°. 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: 205927-03-3Category: copper-catalyst).

(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. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. Category: copper-catalyst

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

Molybdenum Imido Alkylidene Complexes Containing Biphen Ligands that Have Silyl Groups Attached through the 6 and 6′ Methyl Group Carbon Atoms was written by Hultzsch, Kai C.;Bonitatebus, Peter J. Jr.;Jernelius, Jesper;Schrock, Richard R.;Hoveyda, Amir H.. And the article was included in Organometallics in 2001.Electric Literature of C24H34O2 This article mentions the following:

Two new biphenolate ligands were prepared starting from 3,3′-di-tert-butyl-5,5′,6,6′-tetramethyl-2,2′-dimethoxy-1,1′-biphenyl via deprotonation of the 6 and 6′ Me group with KO-t-Bu/n-BuLi, reaction with dichlorodimethylsilane or chlorotrimethylsilane, and deprotection with boron tribromide. Molybdenum imido alkylidene complexes were prepared by treating Mo(NAr)(CHCMe₂Ph)(OTf)₂(DME) with the dipotassium salt of each biphenolate. X-ray crystallog. studies of syn-Mo(NAr)(CHCMe₂Ph)[(rac)-Me₂SiBiphen] and syn-Mo(NAr)(CHCMe₂Ph)[(rac)-TMS₂Biphen] revealed a significantly different geometry of the biphenolate ligands compared to previously structurally characterized four-coordinate biphenolate molybdenum imido alkylidene complexes. The enantiopure complexes were shown to catalyze asym. olefin metathesis with an enantioselectivity comparable to that of Mo(NAr)(CHCMe₂Ph)[(S)-Biphen]. 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. Transition metal-catalyzed chemical transformation of organic electrophiles and organometallic reagents belong to the most important cross-coupling reaction in organic synthesis. Copper of different valence states can be used to catalyze the coupling reaction, especially the Ullmann coupling reaction. Electric Literature of C24H34O2

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

Catalytic Enantioselective Ring-Closing Metathesis by a Chiral Biphen-Mo Complex was written by Alexander, John B.;La, Daniel S.;Cefalo, Dustin R.;Hoveyda, Amir H.;Schrock, Richard R.. And the article was included in Journal of the American Chemical Society in 1998.SDS of cas: 205927-03-3 This article mentions the following:

The enantioselective synthesis of chiral Mo-alkylidene I is reported. This nonracemic transition metal complex bears 5,5′,6,6′-tetramethyl-3,3′-di-tert-butyl-1,1′-biphenyl-2,2′-diol as the chiral ligand, which is resolved by recrystallization of the derived phosphoric acid with optically pure cinchonidine. The catalyst structure is characterized by x-ray crystallog., as well as routine spectroscopic methods. I effects enantioselective ring-closing metathesis efficiently and with excellent selectivity. Depending on the substitution pattern of the reacting alkenes, either the diene substrate or the cycloalkenyl product can be obtained in >92% ee, corresponding to k_rel of up to 58. 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: 205927-03-3SDS of cas: 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. Copper has continued to be one of the most utilized and important transition metal catalysts in synthetic organic chemistry. It is clear from the impact copper catalysis has had on organic synthesis that copper should be considered a first line catalyst for many organic reactions.SDS of cas: 205927-03-3

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