50354-48-8Relevant academic research and scientific papers
Boryl Radical Activation of Benzylic C-OH Bond: Cross-Electrophile Coupling of Free Alcohols and CO2via Photoredox Catalysis
Jiang, Yi-Qian,Lan, Yu,Li, Shi-Jun,Li, Wen-Duo,Li, Yan-Lin,Wu, Yang,Xia, Ji-Bao
, (2022/04/19)
A new strategy for the direct cleavage of the C(sp3)-OH bond has been developed via activation of free alcohols with neutral diphenyl boryl radical generated from sodium tetraphenylborate under mild visible light photoredox conditions. This strategy has been verified by cross-electrophile coupling of free alcohols and carbon dioxide for the synthesis of carboxylic acids. Direct transformation of a range of primary, secondary, and tertiary benzyl alcohols to acids has been achieved. Control experiments and computational studies indicate that activation of alcohols with neutral boryl radical undergoes homolysis of the C(sp3)-OH bond, generating alkyl radicals. After reducing the alkyl radical into carbon anion under photoredox conditions, the following carboxylation with CO2 affords the coupling product.
Rhodium-Catalyzed meta-Selective C?H Carboxylation Reaction of 1,1-Diarylethylenes via Hydrorhodation-Rhodium Migration
Caner, Joaquim,Iwasawa, Nobuharu,Saito, Takanobu,Toriumi, Naoyuki
supporting information, p. 23349 - 23356 (2021/09/18)
A meta-selective C?H carboxylation reaction of 1,1-diarylethylene derivatives with CO2 by using a rhodium catalyst with NaOiPr as a stoichiometric reductant has been achieved. Together with hydrogenation of the ethylene moiety, a carboxyl group was introduced to the meta-position of the aryl ring with high selectivity over the ortho-positions. Experimental and computational mechanistic studies indicate that this carboxylation reaction proceeds via hydrorhodation on the ethylene moiety, followed by 1,4-rhodium migration and successive 1,2-rhodium migration on the aryl ring. The use of a bulky phosphine ligand seems to be the key to this unusual aryl-to-aryl 1,2-rhodium shift.
Room Temperature Coupling of Aryldiazoacetates with Boronic Acids Enhanced by Blue Light Irradiation
da Silva, Amanda F.,Afonso, Marco A. S.,Cormanich, Rodrigo A.,Jurberg, Igor D.
, p. 5648 - 5653 (2020/04/22)
A visible-light-promoted photochemical protocol is reported for the coupling of aryldiazoacetates with boronic acids. This photochemical reaction shows great enhancement compared to the same protocol performed in the absence of light. Except for a few cases, the room temperature coupling in the dark (thermal process) generally does not work. When it does, it is likely to also involve free carbenes as key intermediates. Alternatively, photochemical reactions show a broad scope, can be performed under air and tolerate a wide variety of functional groups. Reaction-evolution monitoring, DFT calculations and control experiments have been used to evaluate the main aspects of this intricate mechanistic scenario. Biologically active molecules Adiphenine, Benactyzine and Aprophen have been prepared as examples of synthetic applications.
Autoinductive conversion of α,α-diiodonitroalkanes to amides and esters catalysed by iodine byproducts under O2
Li, Jing,Lear, Martin J.,Hayashi, Yujiro
, p. 6360 - 6363 (2018/06/21)
Studies to convert nitroalkanes into amides and esters using I2 and O2 revealed in situ-generated iodine species facilitate the homolytic C-I bond cleavage of α,α-diiodonitroalkanes, arguably in an autoinductive or autocatalytic manner. Consequently, we devised a rapid and economical I2/O2-based method to synthesise sterically hindered esters directly from primary nitroalkanes.
Nickel-catalysed direct alkylation of thiophenes via double C(sp3)-H/C(sp2)-H bond cleavage: The importance of KH2PO4
Wang, Xie,Xie, Peipei,Qiu, Renhua,Zhu, Longzhi,Liu, Ting,Li, You,Iwasaki, Takanori,Au, Chak-Tong,Xu, Xinhua,Xia, Yuanzhi,Yin, Shuang-Feng,Kambe, Nobuaki
supporting information, p. 8316 - 8319 (2017/07/26)
A Ni-catalyzed oxidative C-H/C-H cross-dehydrogenative coupling (CDC) reaction was developed for constructing various highly functionalized alkyl (aryl)-substituted thiophenes. This method employs thiophenes and aliphatic (aromatic) amides that contain an 8-aminoquinoline as a removable directing group in the presence of a silver oxidant. The approach enables the facile one-step synthesis of substituted thiophenes with high functional group compatibility via double C-H bond cleavage without affecting C-Br and C-I bonds. DFT calculations verify the importance of KH2PO4 as an additive for promoting C-H bond cleavage and support the involvement of a Ni(iii) species in the reaction.
Nickel-Catalyzed oxidative coupling of unactivated C(sp3)-H bonds in aliphatic amides with terminal alkynes
Luo, Fei-Xian,Cao, Zhi-Chao,Zhao, Hong-Wei,Wang, Ding,Zhang, Yun-Fei,Xu, Xing,Shi, Zhang-Jie
supporting information, p. 18 - 21 (2017/04/04)
In this work, we demonstrated Ni-catalyzed oxidative coupling of unactivated C(sp3)-H bonds with terminal alkynes for construction of C(sp3)-C(sp) bonds to synthesize alkyl-substituted internal alkynes. Different amides exhibited good compatibility. Preliminary mechanistic studies were conducted to account for this alkynylation.
QUINUCLIDINE DERIVATIVES AND THEIR USE AS MUSCARINIC RECEPTOR ANTAGONISTS
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Page/Page column 38, (2009/12/23)
The invention provides compounds of formula (I) wherein R1, R2, R3, Het1, n, Y and X are as defined in the specification, a process for their preparation, pharmaceutical compositions containing them, a process f
PROCESS FOR PRODUCING CARBOXYLIC ACID FROM PRIMARY ALCOHOL
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Page/Page column 5-6, (2009/05/28)
To provide an industrially-useful and environmentally-friendly novel oxidation reaction. A process for producing a carboxylic acid from a primary alcohol, which comprises using an alkali metal chlorite as a co-oxidizing agent and using, as a catalyst, an oxoammonium salt of the formula (1):
Anticholinergics which may be used as medicaments as well as processes for preparing them
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, (2008/06/13)
The present invention relates to new anticholinergics of general formula 1 wherein A, X ? and the groups R1, R2, R3, R4, R5, R6 and R7 may have the meanings given in the claims and in the specification, processes for preparing them and their use as pharamaceutical compositions.
Structures and reactivities of ethylene dication electrophiles
Ohwada, Tomohiko,Yamazaki, Takahisa,Suzuki, Takayoshi,Saito, Shinichi,Shudo, Koichi
, p. 6220 - 6224 (2007/10/03)
1,2-Dicarbonyl compounds such as 2,3-butanedione reacted with benzene in the presence of a strong acid, trifluoromethanesulfonic acid, to give gem-diphenylated ketones in high yield. The monoxime derivative of 1,2-diones also reacted with benzene in the a
