17873-08-4Relevant articles and documents
Preparation of Thioanisole Biscarbanion and C-H Lithiation/Annulation Reactions for the Access of Five-Membered Heterocycles
Zhu, Ranran,Liu, Zheyuan,Chen, Jie,Xiong, Xiaoyu,Wang, Yuntao,Huang, Lin,Bai, Jinshan,Dang, Yanfeng,Huang, Jianhui
supporting information, p. 3161 - 3165 (2018/06/11)
The synthesis, isolation, and X-ray structure of a thioanisole-based trilithium complex are reported. On the basis of the double-lithiation strategy, two novel synthetic methodologies have been developed under mild reaction conditions (room temperature): (1) reactions of lithiated thioanisoles with nitriles give benzoisothiazoles via a [3 + 2]-type of approach with two new bond formations and (2) formation of benzothiophenes from thioanisoles and amides through a [4 + 1] pattern forming 4 new chemical bonds.
Exploring chromium(III)-alkyl bond homolysis with CpCr[(ArNCMe) 2CH](R) complexes
MacLeod, K. Cory,Conway, Julia L.,Patrick, Brian O.,Smith, Kevin M.
scheme or table, p. 17325 - 17334 (2011/03/01)
A range of paramagnetic Cr(III) monohydrocarbyl complexes CpCr[(ArNCMe)2CH](R) (Ar = ortho-disubstituted aryl; R = primary alkyl, trimethylsilylmethyl, benzyl, phenyl, alkenyl, or alkynyl) were synthesized to investigate how varying the steric and electronic properties of the R group affected their propensity for Cr-R bond homolysis. Most complexes were prepared by salt metathesis of known CpCr[(ArNCMe)2CH](Cl) compounds in Et2O with commercial RMgCl solutions, although more sterically demanding combinations of Ar and R groups necessitated the use of halide-free MgR2 reagents and the Cr(III) tosylate or triflate derivatives. Alternative synthetic routes to Cr(III)-R species using the previously reported Cr(II) compounds CpCr[(ArNCMe)2CH] and sources of R? radicals (e.g., BEt3 and air) were also explored. The UV-vis spectra of the CpCr[(ArNCMe)2CH](R) complexes possessed two strong bands with maximum absorbances in the ranges 395-436 nm and 535-582 nm, with the band in the latter range being particularly characteristic of the Cr(III)-R compounds. The Cr-CH2R bond lengths as determined by single-crystal X-ray diffraction were longer than those in the corresponding Cr-CH3 complexes, typically falling in the range 2.10 to 2.13 A. The Cr(III) benzyl compounds displayed longer Cr-CH2Ph distances, while the bond lengths for the alkenyl and alkynyl species were substantially shorter. The rate of Cr-R bond homolysis at room temperature was determined by monitoring the reaction of Cr(III) neopentyl, benzyl, and isobutyl complexes with excess PhSSPh using UV-vis spectroscopy. Although the other primary alkyl, phenyl, and alkenyl compounds did not undergo appreciable homolysis under these conditions, they were cleanly converted to CpCr[(ArNCMe)2CH](SPh) by photolysis.
Reaction of trimethylsilanes with Arenes and Alk-1-enes in the Presence of Lewis Acid: Syntheses of - and (1-Arylthioalk-3-enyl)-trimethylsilanes
Ishibashi, Hiroyuki,Nakatani, Hiroshi,Umei, Yoshizumi,Yamamoto, Wako,Ikeda, Masazumi
, p. 589 - 594 (2007/10/02)
Treatment of equimolar amounts of the trimethylsilanes (2) or (3) and electron-rich arenes with an equimolar amount of Lewis acid (SnCl4 or TiCl4) gave the Friedel-Crafts reaction products, trimethylsilanes (4) or (5), in high yields.Similar treatment of the chlorides (2) or (3) with alk-1-enes gave ene type products, trimethylsilanes (12) or (13), in moderate yields.Some chemical transformations of these products are also described.
