53668-58-9Relevant academic research and scientific papers
Three-Component, Interrupted Radical Heck/Allylic Substitution Cascade Involving Unactivated Alkyl Bromides
Bellotti, Peter,Glorius, Frank,Heidrich, Bastian,Huang, Huan-Ming,Pflüger, Philipp M.,Schwarz, J. Luca
, p. 10173 - 10183 (2020)
Developing efficient and selective strategies to approach complex architectures containing (multi)stereogenic centers has been a long-standing synthetic challenge in both academia and industry. Catalytic cascade reactions represent a powerful means of rapidly leveraging molecular complexity from simple feedstocks. Unfortunately, carrying out cascade Heck-type reactions involving unactivated (tertiary) alkyl halides remains an unmet challenge owing to unavoidable β-hydride elimination. Herein, we show that a modular, practical, and general palladium-catalyzed, radical three-component coupling can indeed overcome the aforementioned limitations through an interrupted Heck/allylic substitution sequence mediated by visible light. Selective 1,4-difunctionalization of unactivated 1,3-dienes, such as butadiene, has been achieved by employing different commercially available nitrogen-, oxygen-, sulfur-, or carbon-based nucleophiles and unactivated alkyl bromides (>130 examples, mostly >95:5 E/Z, >20:1 rr). Sequential C(sp3)-C(sp3) and C-X (N, O, S) bonds have been constructed efficiently with a broad scope and high functional group tolerance. The flexibility and versatility of the strategy have been illustrated in a gram-scale reaction and streamlined syntheses of complex ether, sulfone, and tertiary amine products, some of which would be difficult to access via currently established methods.
Terminal Trifluoromethylation of Ketones via Selective C-C Cleavage of Cycloalkanols Enabled by Hypervalent Iodine Reagents
Wu, Shuang,Li, Junzhao,He, Ru,Jia, Kunfang,Chen, Yiyun
supporting information, p. 9204 - 9209 (2021/11/30)
We report the first terminal trifluoromethylation at aryl and alkyl ketones' ?, or more remote sites via the selective C-C bond cleavage of cycloalkanols. The noncovalent interactions between alcohols and hypervalent iodines(III) reagents were disclosed to activate both alcohols and the Togni I reagent in the dual photoredox/copper catalysis for the transformation. This reaction was scalable to the gram-scale synthesis, applicable to the structurally complex steroid trifluoromethylation, and extendable to the pentafluoroethylation.
Photoinduced Fragmentation Borylation of Cyclic Alcohols and Hemiacetals
Aggarwal, Varinder K.,Madhavachary, Rudrakshula,Noble, Adam,Shu, Chao
supporting information, p. 7213 - 7218 (2020/10/12)
A visible-light photoinduced fragmentation borylation of O-phthalimido cycloalkanols with bis(catecholato)diboron is described. Structurally diverse keto and formyloxy alkyl boronic esters are shown to be conveniently prepared by radical-mediated ring opening of cyclic alcohols and hemiacetals, respectively. The reactions proceed under mild conditions in the absence of additives or photocatalysts, display excellent functional group tolerance, and are shown to allow cleavage of 4-, 5-, 6-, and 7-membered ring substrates. The mechanism proceeds via sequential homolytic N-O and C-C bond cleavages, the latter of which involves β-scission of an alkoxy radical, generating a carbonyl and an alkyl radical that is trapped by the diboron reagent. Spectroscopic studies suggest direct photoexcitation of either the phthalimide or diboron substrates with blue light can initiate a radical chain mechanism.
Copper-Catalyzed and Indium-Mediated Methoxycarbonylation of Unactivated Alkyl Iodides with Balloon CO
Chen, Yanchi,Su, Lei,Gong, Hegui
supporting information, p. 4689 - 4693 (2019/06/27)
This work emphasizes the synthesis of alkyl esters via Cu-catalyzed and In-mediated alkoxycarbonylation of unactivated alkyl iodides in the presence of In or InI. The reactions were suitable for the preparation of primary, secondary, and even tertiary alkyl esters, representing an exceptionally rare example for the creation of quaternary carbon centers upon formation of esters. The preliminary mechanistic studies indicated that alkyl radicals were involved, and Cu/In/CO played a cooperative role in the carbonylation event.
Manganese-Catalyzed Electrochemical Deconstructive Chlorination of Cycloalkanols via Alkoxy Radicals
Allen, Benjamin D. W.,Hareram, Mishra Deepak,Seastram, Alex C.,McBride, Tom,Wirth, Thomas,Browne, Duncan L.,Morrill, Louis C.
supporting information, p. 9241 - 9246 (2019/11/19)
A manganese-catalyzed electrochemical deconstructive chlorination of cycloalkanols has been developed. This electrochemical method provides access to alkoxy radicals from alcohols and exhibits a broad substrate scope, with various cyclopropanols and cyclobutanols converted into synthetically useful β- and γ-chlorinated ketones (40 examples). Furthermore, the combination of recirculating flow electrochemistry and continuous inline purification was employed to access products on a gram scale.
Biologically active compounds
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Page/Page column 27, (2009/05/28)
The present invention relates to compounds of formula (I), and pharmaceutically acceptable salts thereof. The invention further relates to pharmaceutical compositions comprising compounds of formula (I), and the use of such compounds in the treatment of a disease selected from osteoporosis, Paget's disease, Chagas's disease, malaria, gingival diseases, hypercalaemia, metabolic bone disease and diseases involving matrix or cartilate degradation.
