125686-52-4Relevant articles and documents
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 Annulative Synthetic Strategy for Building Triphenylene Frameworks by Multiple C?H Bond Activations
Mathew, Bijoy P.,Yang, Hyun Ji,Kim, Joohee,Lee, Jae Bin,Kim, Yun-Tae,Lee, Sungmin,Lee, Chang Young,Choe, Wonyoung,Myung, Kyungjae,Park, Jang-Ung,Hong, Sung You
supporting information, p. 5007 - 5011 (2017/04/24)
C?H activation is a versatile tool for appending aryl groups to aromatic systems. However, heavy demands on multiple catalytic cycle operations and site-selectivity have limited its use for graphene segment synthesis. A Pd-catal- yzed one-step synthesis of functionalized triphenylene frameworks is disclosed, which proceeds by 2- or 4-fold C?H arylation of unactivated benzene derivatives. A Pd2(dibenzylideneacetone)3 catalytic system, using cyclic diaryliodonium salts as π-extending agents, leads to site-selective inter- and intramolecular tandem arylation sequences. Moreover, N-substituted triphenylenes are applied to a field-effect transistor sensor for rapid, sensitive, and reversible alcohol vapor detection.
Palladium-catalyzed trifluoromethylation of aromatic C-H bond directed by an acetamino group
Zhang, Li-Sheng,Chen, Kang,Chen, Guihua,Li, Bi-Jie,Luo, Shuang,Guo, Qing-Yun,Wei, Jiang-Bo,Shi, Zhang-Jie
supporting information, p. 10 - 13 (2013/04/10)
The first palladium-catalyzed ortho-trifluoromethylation of the aromatic C-H bond directed by an acetamino group is reported. This method provides an efficient and green approach to synthesize the highly biological potential key structure of ortho-CF3 acetanilides and anilines.