611-00-7Relevant articles and documents
Reaction mechanism for the LiCl-mediated directed zinc insertion: A computational and experimental study
Liu, Ching-Yuan,Wang, Xuan,Furuyama, Taniyuki,Yasuike, Shuji,Muranaka, Atsuya,Morokuma, Keiji,Uchiyama, Masanobu
supporting information; experimental part, p. 1780 - 1784 (2010/06/19)
An experimental/computational study on the LiCI-mediated zinc insertion, and the questions of the generation mechanism of Li ion ZnRCIHal, the role of LiCI, and the origin of the regioselectivity in the reaction has been demonstrated. The acceleration of Zn insertion by LiC1 was thermodynamically and kinetically confirmed. The exchange of electrons occurs exclusively among the three atoms, and the charges of the Li and the Cl atoms remain essentially constant during the reaction, indicating that LiCI does not participate in any oxidation/reduction process. The origin of the LiCI effect was investigated by natural bond orbital (NBO) analysis. Origin of the directed oct/to selectivity of the zinc insertion reaction. The theoretical analysis delineated above further advances the understanding of recent zinc insertion chemistry and should contribute to rational design for efficient preparation of functionalized aryl zinc reagents and its application to useful synthetic transformations.
A simple, safe and efficient synthesis of Tyrian purple (6,6'-Dibromoindigo)
Wolk, Joel L.,Frimer, Aryeh A.
experimental part, p. 5561 - 5580 (2010/12/20)
6,6'-Dibromoindigo is a major component of the historic pigment Tyrian purple, arguably the most famous dye of antiquity. Over the last century, chemists have been interested in developing practical syntheses of the compound We describe herein a new, reasonably simple and efficient synthesis of Tyrian purple which opens the way to the production of large quantities of the dye with minimal hazards and at low cost.
Substitution effect on the regioselective halogen/metal exchange of 3-substituted 1,2,5-tribromobenzenes
Menzel, Karsten,Mills, Paul M.,Frantz, Doug E.,Nelson, Todd D.,Kress, Michael H.
, p. 415 - 418 (2008/09/17)
Regioselective halogen/metal exchange reactions using isopropylmagnesium chloride were studied on 3-substituted 1,2,5-tribromoarenes. Seven examples are given.
Acyl sulfonamide anti-proliferatives: Benzene substituent structure-activity relationships for a novel class of antitumor agents
Lobb, Karen L.,Hipskind, Philip A.,Aikins, James A.,Alvarez, Enrique,Cheung, Yiu-Yin,Considine, Eileen L.,De Dios, Alfonso,Durst, Gregory L.,Ferritto, Rafael,Grossman, Cora Sue,Giera, Deborah D.,Hollister, Beth A.,Huang, Zhongping,Iversen, Philip W.,Law, Kevin L.,Li, Tiechao,Lin, Ho-Shen,Lopez, Beatriz,Lopez, Jose E.,Martin Cabrejas, Luisa M.,McCann, Denis J.,Molero, Victoriano,Reilly, John E.,Richett, Michael E.,Shih, Chuan,Teicher, Beverly,Wikel, James H.,White, Wesley T.,Mader, Mary M.
, p. 5367 - 5380 (2007/10/03)
Two closely related diaryl acylsulfonamides were recently reported as potent antitumor agents against a broad spectrum of human tumor xenografts (colon, lung, breast, ovary, and prostate) in nude mice. Especially intriguing was their activity against colorectal cancer xenografts. In this paper, rapid parallel synthesis along with traditional medicinal chemistry techniques were used to quickly delineate the structure-activity relationships of the substitution patterns in both phenyl rings of the acylsufonamide anti-proliferative scaffold. Although the molecular target of the compounds remains unclear, we determined that the vascular endothelial growth factor-dependent human umbilical vein endothelial cells assay in combination with a soft agar disk diffusion assay allowed for optimization of potency in the series. The pharmacokinetic properties and in vivo activity in an HCT116 xenograft model are reported for representative compounds.
ANTITUMOR BENZOYLSULFONAMIDES
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Page 8;9, (2008/06/13)
The present invention provides antitumor compounds of the formula (I); and antitumor methods.
Buttressing Effects Rerouting the Deprotonation and Functionalization of 1,3-Dichloro- and 1,3-Dibromobenzene
Heiss, Christophe,Marzi, Elena,Schlosser, Manfred
, p. 4625 - 4629 (2007/10/03)
A systematic comparison between 1,3-difluorobenzene, 1,3-dichlorobenzene, and 1,3-dibromobenzene did not reveal major differences in their behavior towards strong bases such as lithium diisopropylamide or lithium 2,2,6,6-tetramethyl-piperidide. Thus, all 2,6-dihalobenzoic acids 1 are directly accessible by consecutive treatment with a suitable base and dry ice. In contrast, (2,6-dichlorophenyl)- and (2,6-bromo-phenyl)triethylsilane (2a and 2b) were found to undergo deprotonation at the 5-position (affording acids 3 and, after deprotection, 4), whereas the 1,3-difluoro analog is known to react at the 4-position. The 2,4-dihalobenzoic acids 7 were selectively prepared from either the silanes 2 (by bromination at the 4-position, metalation and carboxylation of the neighboring position, followed by desilylation and debromination) or the 1,3-dihalo-2-iodobenzenes 8 (by base-promoted migration of iodine to the 4-position followed by iodine/magnesium permutation and subsequent carboxylation). Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Substitution Reactions of Phenylated Aza-Heterocycles. Part 2. Bromination of Some 2,5-Diaryl-1,3,4-oxadiazoles
Blackhall, Alexander,Brydon, Donald L.,Javaid, Khalid,Sagar, Anthony J. G.,Smith, David M.
, p. 3485 - 3497 (2007/10/02)
Electrophilic bromination of the title compounds may be achieved using either bromine in oleum, or bromine and potassium bromate in a sulphuric-acetic acid mixture.Under the milder reaction conditions provided by the latter, 2-(p-nitrophenyl)-5-phenyl-1,3,4-oxadiazole (2), the model compound used in this study, is mono- and di-brominated in the phenyl ring.In the first bromination step, all three monobromo-isomers are produced in appreciable amount.The orientation of the second bromination is controlled entirely by the first bromine and not by the oxadiazole substituent: this is confirmed by a separate study of the bromination of the three monobromo-compounds (3a-3c).
