- Double-Fold Ortho and Remote C-H Bond Activation/Borylation of BINOL: A Unified Strategy for Arylation of BINOL
-
A double-fold ortho and remote C-H borylation of BINOL is described. The proposed mechanisms involved electrostatically and sterically directed ortho and remote C-H activation processes, respectively. While B2eg2 (eg = ethylene glyco
- Bisht, Ranjana,Chaturvedi, Jagriti,Pandey, Gajanan,Chattopadhyay, Buddhadeb
-
supporting information
p. 6476 - 6480
(2019/08/20)
-
- Efficient synthesis of 3,3'-diaryl binaphthol through a one-step method
-
The invention relates to a class of catalysis reactions of binaphthol and halogenated aromatic hydrocarbons, particularly to efficient preparation of 3,3'-diaryl binaphthol and 3-Bulkyaryl binaphtholthrough a one-step method, and belongs to the technical field of asymmetric catalysis. A purpose of the present invention is to provide a simple and practical method for preparing 3,3'-diaryl binaphthol through a one-step reaction of inexpensive BINOL and a brominated aromatic hydrocarbon reagent, and is further to provide a simple and rapid method for conveniently preparing 3-aryl binaphthol withhigh steric hindrance.
- -
-
Paragraph 0057-0059
(2018/07/30)
-
- Synthesis and characterization of new biphenolate and binaphtholate rare-earth-metal amido complexes: Catalysts for asymmetric olefin hydroamination/cyclization
-
Monomeric diolate amido yttrium complexes [Y{diolate}{N(SiHMe 2)2}(thf)2] can be prepared in good yield by treating [Y{N(SiHMe2)2}3(thf)2] with either 3,3′-di-tert-butyl-5,5′,6,6′ -tetramethyl-1,1′-biphenyl-2,2′-diol (H2(Biphen)), 3,3′-bis(2,4,6-triisopropylphenyl)-2,2′-dihydroxy-1, 1′-dinaphthyl (H2(Trip2BINO)) or 3,3′-bis(2,6-diisopropylphenyl)-2,2′-dihydroxy-1, 1′-dinaphthyl (H2(DiP2BINO)) in racemic and enantiopure form. The racemic complex [Y(biphen){N(SiHMe2) 2}(thf)2] dimerizes upon heating to give the heterochiral complex (R,S)-[Y(biphen){N(SiHMe2)2}(thf)]2. The corresponding dimeric heterochiral lanthanum complex was the sole product in the reaction of H2(Biphen) with [La{N(SiHMe2) 2}3(thf)2]. Single-crystal X-ray diffraction of both dimeric complexes revealed that the two Ln(biphen){N(SiHMe 2)2}(thf) fragments are connected through bridging phenolate groups of the biphenolate ligands. The two different phenolate groups undergo an intramolecular exchange process in solution leading to their equivalence on the NMR timescale. All complexes were active catalysts for the hydroamination/cyclization of aminoalkynes and aminoalkenes at elevated temperature, with [Y((R)-dip2bino){N(SiHMe2) 2}(thf)2] being the most active one giving enantioselectivities of up to 57% ee. Kinetic resolution of 2-aminohex-5-ene proceeded with this catalyst with 6.4:1 trans selectivity to give 2,5-dimethylpyrrolidine with a krel of 2.6.
- Gribkov, Denis V.,Hultzsch, Kai C.,Hampel, Frank
-
p. 4796 - 4810
(2007/10/03)
-