36971-28-5Relevant academic research and scientific papers
Preparation method of hydroxyphenylboronic acid
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Paragraph 0030-0032, (2020/05/08)
The invention discloses a preparation method of hydroxyphenylboronic acid, which belongs to the technical field of boric acid synthesis in medical intermediates. The method comprises the following steps: starting from bromophenol, carrying out BOC, trimethylsilyl or benzyl protection, forming a Grignard reagent, reacting with borate, or carrying out one-pot reaction with borate and n-butyllithium,and hydrolyzing to obtain hydroxyphenylboronic acid. According to the invention, cheap and easily available protecting groups are adopted, so that the protecting groups are easy to remove during boronation reaction hydrolysis, industrial amplification is easy to realize, batch production is carried out on the scale of dozens of kilograms, and the process stability is good.
Aryne Precursors for Selective Generation of 3-Haloarynes: Preparation and Application to Synthetic Reactions
Kakigi, Kengo,Kawasaki, Yuichi,Miyabe, Hideto,Miyoshi, Shouta,Yoshioka, Eito
, p. 13544 - 13556 (2020/12/15)
The synthesis and reaction of new 3-haloaryne precursors 2a-2h were studied. The ortho-(trimethylsilyl)aryl triflate precursors 2a-2h were prepared by a simple procedure involving O-trimethylsilylation and migration of a trimethylsilyl group followed by triflation. The remarkable feature of new precursors is the selective generation of 3-haloarynes by suppressing the competitive thia-Fries rearrangement, which is the problem in the reaction using the well-known 3-haloaryne precursors. The advantage of new precursor 2a over a typical precursor 1 was confirmed by the direct comparisons in several reactions. The application of precursors 2a-2h to the syntheses of heterocycles was also reported.
A simple and efficient room temperature silylation of diverse functional groups with hexamethyldisilazane using CeO2 nanoparticles as solid catalysts
Anbu, Nagaraj,Vijayan, Chellappa,Dhakshinamoorthy, Amarajothi
, (2019/06/08)
In this study, a mild and efficient method is developed for the silylation of diverse functional groups using CeO2 nanoparticles (n-CeO2) as solid catalysts with hexamethyldisilazane (HMDS) as silylating agent at room temperature. Alcohols, phenols and acids are silylated to their respective silyl derivatives with faster reaction rate while amines and thiols required relatively longer reaction time. Moreover, the solid catalyst is easily be separated from the reaction mixture and recycled more than five times without any obvious decay in its activity. Powder X-ray diffraction (XRD), transmission electron microscope (TEM), UV–vis diffuse reflectance spectra (UV-DRS) and Raman analyses revealed identical structural integrity, particle size, absorption edge and valence state for the reused solid compared to the fresh solid catalyst.
Practical and scaleable syntheses of 3-hydroxythiophenol
Zhang, Mingbao,Ryckman, David,Chen, Guohua,MacMillan, Eric,Duquette, Jason
, p. 112 - 116 (2007/10/03)
3-Hydroxythiophenol is a versatile intermediate for the synthesis of medicinal and heterocyclic compounds. Two novel and practical syntheses of 3-hydroxythiophenol are achieved using readily available and inexpensive starting materials. An overall cost comparison of these syntheses is also given.
Anti-inflammatory piperazinyl-benzyl-tetrazole derivatives and intermediates thereof
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, (2008/06/13)
This invention relates to tetrazoles and their pharmaceutically acceptable salts which are selective agonists for the delta opioid receptor, particularly useful in the treatment of inflammatory diseases such as arthritis, psoriasis, asthma, inflammatory bowel disease, disorders or respiratory function, gastrointestinal disorders such as functional bowel disease and functional GI disorders, of formula (I) wherein R1is H, C2-C6alkanoyl, C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, (C3-C7cycloalkyl)-(C1-C4alkyl), (C1-C4alkoxy)-(C1-C4alkyl), carboxy-(C1-C4alkyl), aryl-(C1-C4alkyl) or heteroaryl-(C1-C4alkyl); R2and R3are each independently H or C1-C4alkyl; R4is selected from (i) H, (ii) a group of the formula R6—(CH2)m—Z—(CH2)n—, where m is 0, 1, 2 or 3, n is 1, 2 or 3, Z is a direct link or O, and R6is —CO2H or —CO2(C1-C4alkyl), and (iii) a group of formula (a) where R7is H or C1-C4alkyl; and R5is hydroxy, C1-C4alkoxy or —NHSO2(C1-C4alkyl); with the proviso that when Z is O, m is 1, 2 or 3 and n is 2 or 3.
3-amin3-arylpropan-1-ol compounds, their preparation and use
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, (2008/06/13)
3-amino-3-arylpropan-1-ol compounds of formula I: R1and R2independently denoting C1-6alkyl, or together denoting a (CH2)2-6ring optionally substituted by phenyl, R3denoting C3-6alkyl, C3-6cycloalkyl, aryl optionally containing heteroatoms and optionally substituted by R6to R8, or a substituted C1-3alkylphenyl of formula XII: ?R4and R5independently denoting C1-6alkyl, C3-6cycloalkyl, phenyl, benzyl, or phenethyl, or together forming a (CH2)3-6or CH2CH2OCH2CH2ring, R6to R8independently denoting H, F, Cl, Br, CHF2, CF3, OH, OCF3, OR14, NR15R16, SR14, phenyl, SO2CH3, SO2CF3, C1-6alkyl, CN, COOR14, or CONR15R16, or together forming a OCH2O, OCH2CH2O, CH═CHO, CH═C(CH3)O or (CH2)4ring, R14denoting C1-6alkyl, phenyl, benzyl, or phenethyl, R15and R16independently denoting H, C1-6alkyl, phenyl, benzyl or phenethyl, and A denoting optionally substituted aryl optionally containing heteroatoms, or a diastereomer or enantiomer or pharmaceutically acceptable salt thereof, and their preparation and use in pharmaceutical compositions.
