35444-94-1Relevant articles and documents
Hypervalent iodine-guided electrophilic substitution: Para-selective substitution across aryl iodonium compounds with benzyl groups
Ahmed, Faiz,Dave, Loma,Dempsey Hyatt, I. F.,Kim, Grace,Li, Tian,Mowdawalla, Cyrus,Pham, Kiet
, p. 1039 - 1045 (2018)
The reactivity of benzyl hypervalent iodine intermediates was explored in congruence with the reductive iodonio-Claisen rearrangement (RICR) to show that there may be an underlying mechanism which expands the reasoning behind the previously known C–C bond
Borane-catalyzed C(sp3)-F bond arylation and esterification enabled by transborylation
Willcox, Dominic R.,Nichol, Gary S.,Thomas, Stephen P.
, p. 3190 - 3197 (2021/04/06)
The activation and functionalization of carbon- fluorine bonds represent a significant synthetic challenge, given the high thermodynamic barrier to C-F bond cleavage. Stoichiometric hydridoborane-mediated C-F functionalization has recently emerged, but is yet to be rendered catalytic. Herein, the borane-catalyzed coupling of alkyl fluorides with arenes (carbon-carbon bond formation) and carboxylic acids (carbon-oxygen bond formation) has been developed using transborylation reactions to achieve catalytic turnover. Successful C-C and C-O coupling across a variety of structurally and electronically differentiated arenes and carboxylic acids was achieved using 9-borabicyclo[3.3.1]nonane (H-B-9-BBN) as the catalyst and pinacolborane (HBpin), with broad functional group tolerance. Experimental and computational studies suggest a mechanistic dichotomy for the carbon-carbon and carbon-oxygen coupling reactions. B-F transborylation (B-F/B-H metathesis) between F-B-9-BBN and HBpin enabled catalytic turnover for carbon-carbon bond formation, whereas direct exchange between the alkyl fluoride and acyloxyboronic ester (C-F/B-O metathesis) was proposed for carbon-oxygen coupling, where H-B-9-BBN catalyzed the dehydrocoupling of the carboxylic acid with HBpin.
para-Selective Benzylation of Aryl Iodides by the in situ Preparation of ArIF2: a Hypervalent Iodine-Guided Electrophilic Substitution
Chaudhry, Azka,Hyatt, I. F. Dempsey,Im, Haram,Jones, Taro J.,Noorollah, Jennifer,Siddiqi, Fatima,Singh, Nirvanie,Spatola, Nicholas R.
supporting information, (2020/04/16)
Hypervalent iodine-guided electrophilic substitution (HIGES) was described previously for the para-selective benzylation of aryl-λ3-iodane diacetates. One drawback of the method was the synthesis and isolation of hypervalent iodine starting mat
Synthesis of Polysubstituted Iodoarenes Enabled by Iterative Iodine-Directed para and ortho C?H Functionalization
Wu, Yichen,Bouvet, Sébastien,Izquierdo, Susana,Shafir, Alexandr
supporting information, p. 2617 - 2621 (2019/01/04)
Among halogenated aromatics, iodoarenes are unique in their ability to produce the bench-stable halogen(III) form. Earlier, such iodine(III) centers were shown to enable C?H functionalization ortho to iodine via halogen-centered rearrangement. The broader implications of this phenomenon are explored by testing the extent of an unusual iodane-directed para C?H benzylation, as well as by developing an efficient C?H coupling with sulfonyl-substituted allylic silanes. Through the combination of the one-shot nature of the coupling event and the iodine retention, multisubstituted arenes can be prepared by sequentially engaging up to three aromatic C?H sites. This type of iodine-based iterative synthesis will serve as a tool for the formation of value-added aromatic cores.
Simple and Efficient Generation of Aryl Radicals from Aryl Triflates: Synthesis of Aryl Boronates and Aryl Iodides at Room Temperature
Liu, Wenbo,Yang, Xiaobo,Gao, Yang,Li, Chao-Jun
supporting information, p. 8621 - 8627 (2017/07/06)
Despite the wide use of aryl radicals in organic synthesis, current methods to prepare them from aryl halides, carboxylic acids, boronic acids, and diazonium salts suffer from limitations. Aryl triflates, easily obtained from phenols, are promising aryl radical progenitors but remain elusive in this regard. Inspired by the single electron transfer process for aryl halides to access aryl radicals, we developed a simple and efficient protocol to convert aryl triflates to aryl radicals. Our success lies in exploiting sodium iodide as the soft electron donor assisted by light. This strategy enables the scalable synthesis of two types of important organic molecules, i.e., aryl boronates and aryl iodides, in good to high yields, with broad functional group compatibility in a transition-metal-free manner at room temperature. This protocol is anticipated to find potential applications in other aryl-radical-involved reactions by using aryl triflates as aryl radical precursors.
Feedstocks to Pharmacophores: Cu-Catalyzed Oxidative Arylation of Inexpensive Alkylarenes Enabling Direct Access to Diarylalkanes
Vasilopoulos, Aristidis,Zultanski, Susan L.,Stahl, Shannon S.
, p. 7705 - 7708 (2017/06/20)
A Cu-catalyzed method has been identified for selective oxidative arylation of benzylic C-H bonds with arylboronic esters. The resulting 1,1-diarylalkanes are accessed directly from inexpensive alkylarenes containing primary and secondary benzylic C-H bonds, such as toluene or ethylbenzene. All catalyst components are commercially available at low cost, and the arylboronic esters are either commercially available or easily accessible from the commercially available boronic acids. The potential utility of these methods in medicinal chemistry applications is highlighted.
Hypophosphorous acid-iodine: A novel reducing system. Part 2: Reduction of benzhydrols to diarylmethylene derivatives
Gordon, Paul E.,Fry, Albert J.
, p. 831 - 833 (2007/10/03)
A mixture of hypophosphorous acid (H3PO2) and iodine in acetic acid reduces a variety of substituted benzhydrols to the corresponding methylene derivatives in very high yields. The active reducing agent is hydrogen iodide generated by reaction between iodine and hypophosphorous acid.
Iodination of Aryltrimethylsilanes: A Mild Approach to Iodophenylalanine
Wilson, Stephen R.,Jacob, Linda A.
, p. 4833 - 4836 (2007/10/02)
Phenylalanine has been labeled with the radioactive isotopes of iodine by using harsh conditions or toxic mercury compounds.A mild method of incorporating iodine onto an aryl ring was developed that combines two methods that have been used separately for the production of aryl iodides: (1) the use of the Lewis acid to activate the elecrophile, I2, and (2) the use of a trimethylsilyl group to direct the introduction of iodine.Simple aryltrimethylsilanes and a phenylalanine-containing peptide were successfully iodinated by this method.
