17763-95-0Relevant articles and documents
A site-selective and stereospecific cascade Suzuki-Miyaura annulation of alkyl 1,2-bisboronic esters and 2,2′-dihalo 1,1′-biaryls
Willems, Suzanne,Toupalas, Georgios,Reisenbauer, Julia C.,Morandi, Bill
supporting information, p. 3909 - 3912 (2021/04/26)
A cascade Suzuki-Miyaura cross-coupling giving rise to 9,10-dihydrophenanthrenes has been developed. Using biaryls with unsymmetrical substitution-pattern full site-selectivity was observed. Furthermore, this cross-coupling of an alkyl 1,2-bisboronic pinacol ester proceeds through the challenging coupling of a secondary boronate with complete stereoretention.
Carboxylation of Aryl Triflates with CO2 Merging Palladium and Visible-Light-Photoredox Catalysts
Bhunia, Samir Kumar,Das, Pritha,Nandi, Shantanu,Jana, Ranjan
, p. 4632 - 4637 (2019/06/27)
We report herein a visible-light-promoted, highly practical carboxylation of readily accessible aryl triflates at ambient temperature and a balloon pressure of CO2 by the combined use of palladium and photoredox Ir(III) catalysts. Strikingly, the stoichiometric metallic reductant is replaced by a nonmetallic amine reductant providing an environmentally benign carboxylation process. In addition, one-pot synthesis of a carboxylic acid directly from phenol and modification of estrone and concise synthesis of pharmaceutical drugs adapalene and bexarotene have been accomplished via late-stage carboxylation reaction. Furthermore, a parallel decarboxylation-carboxylation reaction has been demonstrated in an H-type closed vessel that is an interesting concept for the strategic sector. Spectroscopic and spectroelectrochemical studies indicated electron transfer from the Ir(III)/DIPEA combination to generate aryl carboxylate and Pd(0) for catalytic turnover.
A Binaphthyl-Based Scaffold for a Chiral Dirhodium(II) Biscarboxylate Ligand with α-Quaternary Carbon Centers
Chen, Po-An,Setthakarn, Krit,May, Jeremy A.
, p. 6155 - 6161 (2017/09/15)
A chiral dirhodium(II) paddlewheel complex has been synthesized from biscarboxylate ligands derived from BINOL, and the resulting complex has been used in enantioselective carbene/alkyne cascade reactions. The ligand design was guided by requirements of α
Nickel-Catalyzed Cyanation of Aryl Chlorides and Triflates Using Butyronitrile: Merging Retro-hydrocyanation with Cross-Coupling
Yu, Peng,Morandi, Bill
supporting information, p. 15693 - 15697 (2017/12/02)
We describe a nickel-catalyzed cyanation reaction of aryl (pseudo)halides that employs butyronitrile as a cyanating reagent instead of highly toxic cyanide salts. A dual catalytic cycle merging retro-hydrocyanation and cross-coupling enables the conversion of a broad array of aryl chlorides and aryl/vinyl triflates into their corresponding nitriles. This new reaction provides a strategically distinct approach to the safe preparation of aryl cyanides, which are essential compounds in agrochemistry and medicinal chemistry.
Efficient synthesis of biscarbazoles by palladium-catalyzed twofold C-N coupling and C-H activation reactions
Hung, Tran Quang,Thang, Ngo Ngoc,Hoang, Do Huy,Dang, Tuan Thanh,Villinger, Alexander,Langer, Peter
supporting information, p. 2596 - 2605 (2014/04/17)
A new and efficient strategy for the synthesis of 3,9′- and 2,9′-biscarbazoles was developed. Our strategy relies on the cyclization of 1,1′-biphenyl-2,2′-diyl bis(trifluoromethanesulfonate) with 4- or 3-anisidine, transformation of the methoxy to a triflate group and subsequent oxidative Pd-catalyzed cyclization with various anilines. This journal is the Partner Organisations 2014.
Phosphine-oxazoline ligands with an axial-unfixed biphenyl backbone: the effects of the substituent at oxazoline ring and P phenyl ring on Pd-catalyzed asymmetric allylic alkylation
Tian, Fengtao,Yao, Dongmei,Zhang, Yong Jian,Zhang, Wanbin
experimental part, p. 9609 - 9615 (2010/02/27)
A novel kind of chiral phosphine-oxazoline ligands 3 with an axial-unfixed biphenyl backbone bearing different substituent on oxazoline ring and P phenyl ring was prepared. These ligands exist as a mixture of two diastereomers in equilibrium in solution.
A novel axially chiral phosphine-oxazoline ligand with an axis-unfixed biphenyl backbone: Preparation, complexation, and application in an asymmetric catalytic reaction
Zhang, Wanbin,Xie, Fang,Yoshinaga, Hidefumi,Kida, Toshiyuki,Nakatsuji, Yohji,Ikeda, Isao
, p. 1185 - 1188 (2007/10/03)
A novel chiral phosphine-oxazoline ligand 3 with an axis-unfixed biphenyl backbone was prepared. This ligand existed as a mixture of two diastereomers in equilibrium in solution. However, when it was coordinated with palladium(II), only one of the two kin
General synthetic route to chiral flexible biphenylphosphine ligands: The use of a chiral additive enables the preparation and observation of metal complexes incorporating the enantiopure form
Mikami, Koichi,Aikawa, Kohsuke,Korenaga, Toshinobu
, p. 243 - 245 (2007/10/03)
equation presented The enantio-and diastereomerically pure metal complex of a chirally flexible BIPHEP ligand is obtained through enantiomer-selective coordination of a BIPHEP-Ru complex with enantiopure 3,3′-dimethyldiaminobinaphthyl, DM-DBN, followed by
Highly enantioselective hydroformylation of olefins catalyzed by rhodium(I) complexes of new chiral phosphine-phosphite ligands
Nozaki, Kyoko,Sakai, Nozomu,Nanno, Tetsuo,Higashijima, Takanori,Mano, Satoshi,Horiuchi, Toshihide,Takaya, Hidemasa
, p. 4413 - 4423 (2007/10/03)
A new chiral phosphine-phosphite ligand, (R)-2-(diphenylphosphino)- 1,1'-binaphthalen-2'-yl (S)-1,1'-binaphthalene-2,2'-diyl phosphite [(R,S)- BINAPHOS, (R,S)-2a], was synthesized. Its Rh(I) complex was prepared, and its structure has been characterized by 1H and 31P NMR spectroscopy. Using Rh(I) complexes of (R,S)-2a and its enantiomer, highly enantioselective hydroformylation of styrene has been performed (94% ee, iso/normal = 88/12). The catalyst system was also effective for a variety of other olefins. Some other phosphine-phosphite ligands bearing 1,1'-binaphthyl and biphenyl backbones, such as (S)-3,3'-dichloro-6-(diphenylphosphino)-2,2',4,4'- tetramethylbiphenyl-6'-yl (R)-1,1'-binaphthalene-2,2'-diyl phosphite [(S,R)- BIPHEMPHOS. (S,R)-5a], (R,R)-2a, (R,S)-2b, (R)-2c, and (R)-5b, were tested for asymmetric hydroformylation. The results indicate that the sense of enantioface selection for the prochiral olefins is mainly determined by the absolute configuration of the phosphine site, for example, the (R)-2- (diphenylphosphino)-1,1'-binaphthalen-2'-yl group in (R,S)-2a. The relative configurations of the two biaryl groups in the phosphine-phosphites play crucial roles in the degree of the enantioselectivities, that is, the (R,S)- isomer generally gives products in high ee's and the (R*,R*)-isomer does in low ee's. Treatment of Rh(acac)[(R,S)-2a] with a 1:1 mixture of carbon monoxide and hydrogen gave a hydridorhodium complex. RhH-(CO)2[(R,S)-2a], as a single species. Trigonal bipyramidal structure is suggested for this complex, in which the hydride and the phosphite moiety are located at the apical positions and the phosphine and the two carbonyls occupy the equatorial positions. The interchange of the phosphine and the phosphite sites with each other through rapid pseudorotations has not been observed in RhH(CO)2[(R,S)-2a]. The structural deviations of the monohydride complexes from an ideal trigonal bipyramid seem to be larger in (R*,R*)-isomers than in the corresponding (R*,S*)-isomers. The existence of only one active species involved in the Rh(1)-(R,S)-2a-catalyzed hydroformylation has been manifested by the plot of ln([R]/[S]) of the hydroformylation product vs the reciprocals of the reaction temperatures. The higher thermodynamic stability of Rh(acac)[(R,S)-2a] than its diastereomer Rh(acac)[(R,R)-2a] is demonstrated in relation to the restricted configuration of (R)-2c to (R,S)- 2c in its complex formation with Rh(1).
Synthesis of New Chiral Phosphinephosphites Having 2-Diphenylphosphinobiphenyl-2'-yl Backbone and Their Use in Rh(I)-Catalyzed Asymmetric Hydroformylations
Higashizima, Takanori,Sakai, Nozomu,Nozaki, Kyoko,Takaya, Hidemasa
, p. 2023 - 2026 (2007/10/02)
New chiral phosphinephosphites (R)-(5,5'-dichloro-2-diphenylphosphino-4,4',6,6'-tetramethylbiphenyl-2'-yl)(S)-1,1'-binaphthalen-2,2'-diyl)phosphite and its enantiomer (S,R)-BIPHEMPHOS have been synthesized from 5,5'-dichloro-4,4',6,6'-tetramethyl-2,2'-biphenyldiol in enantiomerically pure form.Their Rh(I) complexes have been shown to be highly efficient catalysts for asymmetric hydroformylations of a variety of olefinic substrates.The corresponding phosphinephosphites derived from 2,2'-biphenyldiol were also tested as ligands for asymmetric hydroformylation.