52807-27-9Relevant academic research and scientific papers
Pd-Catalyzed ipso, meta-Dimethylation of ortho-Substituted Iodoarenes via a Base-Controlled C-H Activation Cascade with Dimethyl Carbonate as the Methyl Source
Wu, Zhuo,Wei, Feng,Wan, Bin,Zhang, Yanghui
supporting information, p. 4524 - 4530 (2021/05/04)
A methyl group can have a profound impact on the pharmacological properties of organic molecules. Hence, developing methylation methods and methylating reagents is essential in medicinal chemistry. We report a palladium-catalyzed dimethylation reaction of ortho-substituted iodoarenes using dimethyl carbonate as a methyl source. In the presence of K2CO3 as a base, iodoarenes are dimethylated at the ipso- and meta-positions of the iodo group, which represents a novel strategy for meta-C-H methylation. With KOAc as the base, subsequent oxidative C(sp3)-H/C(sp3)-H coupling occurs; in this case, the overall transformation achieves triple C-H activation to form three new C-C bonds. These reactions allow expedient access to 2,6-dimethylated phenols, 2,3-dihydrobenzofurans, and indanes, which are ubiquitous structural motifs and essential synthetic intermediates of biologically and pharmacologically active compounds.
Facile and practical synthesis of π-extended oxepins by benzannulation and intramolecular cyclization
Umeda, Rui,Shimizu, Yuji,Ida, Yuta,Ikeshita, Masahiro,Suzuki, Shuichi,Naota, Takeshi,Nishiyama, Yutaka
, p. 183 - 186 (2018/12/11)
π-Extended oxepins 1 and dimer 8 were synthesized by the benzannulation of the corresponding asymmetric diarylacetylene derivatives and 2-(phenylethynyl)benzaldehyde followed by the Cu-catalyzed intramolecular cyclization. The optical properties of the π-extended oxepins 1 and 8 are also investigated.
Site-Selective C–H Functionalization of (Hetero)Arenes via Transient, Non-symmetric Iodanes
Fosu, Stacy C.,Hambira, Chido M.,Chen, Andrew D.,Fuchs, James R.,Nagib, David A.
supporting information, p. 417 - 428 (2019/02/14)
Fosu, Hambira, and colleagues describe the direct C–H functionalization of medicinally relevant arenes or heteroarenes. This strategy is enabled by transient generation of reactive, non-symmetric iodanes from anions and PhI(OAc)2. The site-selective incorporation of Cl, Br, OMs, OTs, and OTf to complex molecules, including within medicines and natural products, can be conducted by the operationally simple procedure included herein. A computational model for predicting site selectivity is also included. The discovery of new medicines is a time- and labor-intensive process that frequently requires over a decade to complete. A major bottleneck is the synthesis of drug candidates, wherein each complex molecule must be prepared individually via a multi-step synthesis, frequently requiring a week of effort per molecule for thousands of candidates. As an alternate strategy, direct, post-synthetic functionalization of a lead candidate could enable this diversification in a single operation. In this article, we describe a new method for direct manipulation of drug-like molecules by incorporation of motifs with either known pharmaceutical value (halides) or that permit subsequent conversion (pseudo-halides) to medicinally relevant analogs. This user-friendly strategy is enabled by combining commercial iodine reagents with salts and acids. We expect this simple method for selective, post-synthetic incorporation of molecular diversity will streamline the discovery of new medicines. A strategy for C–H functionalization of arenes and heteroarenes has been developed to allow site-selective incorporation of various anions, including Cl, Br, OMs, OTs, and OTf. This approach is enabled by in situ generation of reactive, non-symmetric iodanes by combining anions and bench-stable PhI(OAc)2. The utility of this mechanism is demonstrated via para-selective chlorination of medicinally relevant arenes, as well as site-selective C–H chlorination of heteroarenes. Spectroscopic, computational, and competition experiments describe the unique nature, reactivity, and selectivity of these transient, unsymmetrical iodanes.
An alternative to the Sandmeyer approach to aryl iodides
Hu, Bao,Miller, William H.,Neumann, Kiel D.,Linstad, Ethan J.,DiMagno, Stephen G.
, p. 6394 - 6398 (2015/04/22)
Iodoarenes are important synthons for a wide range of organic transformations. Here we report a general strategy to prepare singly iodinated electron-rich aromatic compounds through the intermediacy of diaryliodonium salts. This process, which incorporates a phase separation that greatly simplifies product purification, is an attractive replacement for the Sandmeyer approach to iodoarenes that are otherwise difficult to access.
Regioselective heterohalogenation of 4-halo-anisoles via a series of sequential ortho-aluminations and electrophilic halogenations
Conway, Ben,Crosbie, Elaine,Kennedy, Alan R.,Mulvey, Robert E.,Robertson, Stuart D.
supporting information; experimental part, p. 4674 - 4676 (2012/06/16)
As the aluminate base [LiAl(TMP)2(iBu)2] 1 displays halogen tolerance towards substituted aromatics, 4-halo-anisoles have been ortho-aluminated and electrophilically quenched to form synthetically useful multi-heterohalogenated aniso
Regioselective iodination of aromatic compounds with potassium iodide in the presence of benzyltriphenylphosphonium perchlorate
Albadi, Jalal,Abedini, Masoumeh,Iravani, Nasir
experimental part, p. 261 - 264 (2012/05/07)
A simple and efficient method for the selective iodination of various aromatic compounds by using potassium iodide in the presence of benzyltriphenylphosphonium perchlorate, is reported. This method provides several advantages such as good selectivity between ortho and para positions of aromatic compounds and high yields of the products.
Diatomite-supported Pd nanoparticles: An efficient catalyst for Heck and Suzuki reactions
Zhang, Zuhui,Wang, Zhiyong
, p. 7485 - 7487 (2007/10/03)
The Pd nanoparticles immobilized on natural diatomite were achieved by a simple procedure. The catalysts are highly active for Heck and Suzuki reactions and can be recovered and reused many times. The catalytic process was also investigated.
Room temperature regioselective iodination of aromatic ethers mediated by Selectfluor(TM) reagent F-TEDA-BF4
Zupan, Marko,Iskra, Jernej,Stavber, Stojan
, p. 6305 - 6306 (2007/10/03)
Monosubstituted phenyl ethers were regioselectively iodinated with a mixture of iodine and F-TEDA in acetonitrile at room temperature at the para position, while 1-methoxy-4-substituted benzene derivatives were converted to 2-iodo products in high yield.
