98527-70-9Relevant academic research and scientific papers
A process for preparing aldehyde group benzene boric acid
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Paragraph 0023; 0024; 0025, (2017/07/04)
The invention discloses a method for preparing formyl phenylboronic acid, which comprises the following steps: heating halogenated phenylboronic acid in toluene or heptane under reflux for dewatering to form a tripolymer, mixing the tripolymer with dimethylformamide, dropwisely adding n-butyllithium at low temperature to react by a one-pot process, hydrolyzing with hydrochloric acid, and recrystallizing to obtain the formyl phenylboronic acid. The method is simple to operate, avoids the process of separating the intermediate after formyl protection in the conventional technique, has high universality, can obtain favorable yield for ortho-, meta- and para- formyl phenylboronic acids, and is beneficial to scale-up production.
A process for preparing carboxyl boric acid
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Paragraph 0025; 0026, (2017/08/25)
The invention discloses a method for preparing carboxyl phenylboronic acid. The method comprises the following steps of starting from halogenated phenylboronic acid, heating, refluxing and dehydrating in a solvent to form a tripolymer; then forming a grignard reagent of corresponding tripolymer from tripolymer and magnesium metal or isopropyl magnesium chloride; then introducing a carbon dioxide gas at low temperature or adding dry ice for reaction; after the reaction is finished, adding hydrochloric acid, regulating till pH is equal to 2-3, and hydrolyzing; and precipitating carboxyl phenylboronic acid, filtering, and drying to obtain a pure product. The method disclosed by the invention can achieve good yield on ortho-position, meta-position and para-position carboxyl phenylboronic acid, is simple in used reagent and easy and convenient to operate and prevents the generation of a large quantity of solid wastes.
Palladium(II)-Catalyzed Enantioselective Synthesis of α-(Trifluoromethyl)arylmethylamines
Johnson, Thomas,Luo, Bo,Lautens, Mark
, p. 4923 - 4930 (2016/07/06)
We describe a method for the synthesis of α-(trifluoromethyl)arylmethylamines that consists of the palladium(II)-catalyzed addition of arylboroxines to imines derived from trifluoroacetaldehyde. Palladium acetate is used as a catalyst with electron-neutral or electron-rich arylboroxines, and it was found that addition of an ammonium or silver salt was crucial to promote the reaction of electron-poor boroxines. With (S)-t-Bu-PyOX as the chiral ligand, this method delivers a variety of α-trifluoromethylated amines in 57-91% yield and with greater than 92% ee in most cases.
Oxidative coupling of aryl boron reagents with sp3-carbon nucleophiles: The enolate chan–evans–lam reaction
Moon, Patrick J.,Halperin, Heather M.,Lundgren, Rylan J.
supporting information, p. 1894 - 1898 (2016/12/03)
Reported is a versatile new oxidative method for the arylation of activated methylene species. Under mild reaction conditions (RT to 40°C), Cu(OTf)2mediates the selective coupling of functionalized aryl boron species with a variety of stabilized sp3-nucleophiles. Tertiary malonates and amido esters can be employed as substrates to generate quaternary centers. Complementing either traditional cross-coupling or SNAr protocols, the transformation is chemoselective in the presence of halogen electrophiles, including aryl bromides and iodides. Substrates bearing amide, sulfonyl, and phosphonyl groups, which are not amenable to coupling under mild Hurtley-type conditions, are suitable reaction partners.
Rh-catalyzed addition of arylboroxines to cyclic N -(Isopropanesulfinyl) ketimines
Jung, Hyung Hoon,Buesking, Andrew W.,Ellman, Jonathan A.
, p. 9593 - 9600,8 (2012/12/12)
Arylboroxines, which are easily accessed by drying commercially available arylboronic acids, are added to N-(isopropanesulfinyl)ketimines derived from cyclohexanone, N-Boc-piperidin-4-one, and tetrahydropyran-4-one in high yields and with excellent functional group compatibility via rhodium catalysis. These results contrast with additions to the corresponding ketimines incorporating the larger N-tert-butanesulfinyl group, which give considerably lower yields. Efficient two-step preparation of racemic isopropanesulfinamide from inexpensive isopropyl disulfide and recycling of the isopropanesulfinyl group from the addition products are also described.
Rh-catalyzed addition of arylboroxines to cyclic N -(Isopropanesulfinyl) ketimines
Jung, Hyung Hoon,Buesking, Andrew W.,Ellman, Jonathan A.
, p. 9593 - 9600 (2013/01/15)
Arylboroxines, which are easily accessed by drying commercially available arylboronic acids, are added to N-(isopropanesulfinyl)ketimines derived from cyclohexanone, N-Boc-piperidin-4-one, and tetrahydropyran-4-one in high yields and with excellent functional group compatibility via rhodium catalysis. These results contrast with additions to the corresponding ketimines incorporating the larger N-tert-butanesulfinyl group, which give considerably lower yields. Efficient two-step preparation of racemic isopropanesulfinamide from inexpensive isopropyl disulfide and recycling of the isopropanesulfinyl group from the addition products are also described.
Catalyzed asymmetric aryl transfer reactions to aldehydes with boroxines as aryl source
Wu, Xiaoyu,Liu, Xinyuan,Zhao, Gang
, p. 2299 - 2305 (2007/10/03)
Asymmetric aryl transfer of triphenylboroxin to a set of aryl aldehydes has been carried out in the presence of chiral amino alcohols derived from (S)-proline with high enantioselectivity. Substituted phenyl boroxins were also used as aryl source in asymmetric arylation of benzaldehyde.
