138604-66-7Relevant academic research and scientific papers
Axially Chiral 1,1'-Binaphthyl-2-Carboxylic Acid (BINA-Cox) as Ligands for Titanium-Catalyzed Asymmetric Hydroalkoxylation
Blazejak, Max,Helmbrecht, Sebastian L.,Hintermann, Lukas,Schlüter, Johannes
supporting information, (2020/04/15)
Axially chiral, enantiopure 1,1'-binaphthyl-2-carboxylic acids (BINA-Cox) have recently been introduced as chiral ligands for transition metal catalysis. Together with equimolar, co-catalytic amounts of Ti(OiPr)4 and water they form an in situ catalyst that performs the asymmetric catalytic hydroalkoxylation of 2-allylphenols to 2-methylcoumarans at high temperature (240 °C, microwave heating). The synthesis of reference ligand 2'-MeO-BINA-Cox (L1) has been optimized and performed at molar scale. Synthetic routes have been developed to access a variety of substituted BINA-Cox ligands (>30 examples), which have been tested for ligand effects on the reference asymmetric cyclization of 2-allylphenol. The substrate range of asymmetric catalytic hydroalkoxylation has been explored through systematic substrate structure variations to define scope and limitations of the titanium-catalyzed process. The new substrates 2-(1-vinylcycloalkyl)phenols (1j, 1k), 2-(2-vinylphenyl)propan-2-ol (1t), and 2'-vinyl-[1,1'-biphenyl]-2-ol (1u) are shown to undergo asymmetric catalytic cyclization to benzodihydrofurans and benzo[c]chromene, respectively.
A recyclable chiral RU catalyst for enantioselective olefin metathesis. Efficient catalytic asymmetric ring-opening/cross metathesis in air
Van Veldhuizen, Joshua J.,Garber, Steven B.,Kingsbury, Jason S.,Hoveyda, Amir H.
, p. 4954 - 4955 (2007/10/03)
The synthesis and structure of a new chiral bidentate imidazolinylidene ligand and a derived chiral Ru-based carbene are disclosed. The Ru complex is stereogenic at the metal center; it can be prepared in >98% diastereoselectivity and purified by silica gel chromatography with undistilled solvents. The air-stable Ru complex efficiently catalyzes ring-closing and ring-opening metathesis and is recyclable. The chiral complex is highly effective (0.5-10 mol % loading) in promoting enantioselective ring-opening/cross metathesis reactions (up to >98% ee). These enantioselective transformations can be effected in air, with unpurified solvent and with substrates that would only polymerize with Mo-based catalysts. Copyright
Asymmetric synthesis of helical poly(quinoxaline-2,3-diyl)s by palladium-mediated polymerization of 1,2-diisocyanobenzenes: Effective control of the screw-sense by a binaphthyl group at the chain-end
Ito, Yoshihiko,Miyake, Toshiyuki,Hatano, Seiji,Shima, Ryoto,Ohara, Takafumi,Suginome, Michinori
, p. 11880 - 11893 (2007/10/03)
Aromatizing polymerization of 1,2-diisocyanobenzene derivatives was mediated by optically active organopalladium(II) complexes bearing 1,1'- binaphth-2-yl groups to give optically active poly(quinoxaline-2,3-diyl)s with varying screw-sense selectivities, which crucially depended upon the substituents on the binaphthyl groups. The most effective catalyst, which has 7'-methoxy-1,1'-binaphthyl group, induced the formation of a single screw- sense. Isolation and structural analyses (single-crystal X-ray diffraction and 1H NMR spectroscopy) of intermediary [oligo(quinoxalinyl)]palladium complexes revealed that the screw-sense selection in the polymerization may be decisively governed by the diastereomeric ratios of the (terquinoxalinyl)palladium(II) complex intermediate.
Nucleophilic Aromatic Substitution on 1-Alkoxy-2-naphthoates with 1-Naphthyl Grignard Reagents. A Practical and Convenient Asymmetric Synthesis of 1,1'-Binaphthyl-2-carboxylates
Hattori, Tetsutaro,Hotta, Hiroki,Suzuki, Takatsugu,Miyano, Sotaro
, p. 613 - 622 (2007/10/02)
1-Naphthyl Grignard reagents efficiently displace the 1-alkoxyl group of 1-alkoxy-2-naphthoic esters to provide an easy access to the corresponding 1,1'-binaphthyl-2-carboxylates in excellent yields; isopropyl ester is bulky enough to prevent the Grignard
An Efficient Asymmetric Synthesis of Atropisomeric 1,1'-Binaphthyls via Nucleophilic Aromatic Substitution Reaction
Suzuki, Takatsugu,Hotta, Hiroki,Hattori, Tetsutaro,Miyano, Sotaro
, p. 807 - 810 (2007/10/02)
High levels of asymmetric induction (up to 98percent optical yield) were achieved in the joining of two naphthalene rings by the nucleophilic displacement of 1-menthoxyl group of 1-(-)-menthoxy-2-naphthoates (1) with 1-naphthyl Grignard reagents.Also repo
Facile Synthesis of 1,1'-Binaphthyl-2-carboxylates via Nucleophilic Aromatic Substitution of 1-Methoxy-2-naphthoic Esters by 1-Naphthyl Grignard Reagents
Hotta, Hiroki,Suzuki, Takatsugu,Miyano, Sotaro
, p. 143 - 144 (2007/10/02)
Grignard reagents formed from 1-bromonaphthalenes smoothly displaced the 1-methoxyl group of 1-methoxy-2-naphthoic esters to provide a facile route of 1,1'-binaphthyl-2-carboxylic acids in excellent yields; the reaction of (S)-1-phenylethyl esters caused
Optical Resolution of 2'-Methoxy-1,1'-binaphthyl-2-carboxylic Acid, and Application to Chiral Derivatizing Agent for HPLC Separation of Enantiomeric Alcohols and Amines
Miyano, Sotaro,Okada, Shin-ichi,Hotta, Hiroki,Takeda, Masayuki,Kabuto, Chizuko,Hashimoto, Harukichi
, p. 1528 - 1533 (2007/10/02)
Racemic 2'-methoxy-1,1'-binaphthyl-2-carboxylic acid was separated on a multi-gram scale into its antipodes via silica-gel column chromatography followed by alkine hydrolysis of the diastereomeric esters prepared from (R)-1-phenylethanol or (-)-menthol.The molecular structure of (-)-menthyl (aS)-2'-methoxy-1,1'-binaphthyl-2-carboxylate was determined by single-crystal X-ray analysis.The (aS)-acid was converted to crystalline acid chloride, which was conveniently utilized as efficient chiral derivatizing agent for differentiation of enantiomeric alcohols and amines by high-performance liquid chromatography on silica gel.The elution behavior of a pair of diastereomeric esters or amides was explained by the steric interactions between the solutes and the silica-gel stationary phase on the basis of the X-ray analysis.
