56763-59-8Relevant academic research and scientific papers
Dispersion-Controlled Regioselective Acid-Catalyzed Intramolecular Hydroindolation of cis-Methindolylstyrenes to Access Tetrahydrobenzo[ cd]indoles
Cai, Xiao,Tohti, Anargul,Ramirez, Cristian,Harb, Hassan,Fettinger, James C.,Hratchian, Hrant P.,Stokes, Benjamin J.
, p. 1574 - 1577 (2019)
Readily prepared cis-β-(α′,α′-dimethyl)-4′-methindolylstyrenes undergo acid-catalyzed intramolecular hydroindolation to afford tetrahydrobenzo[cd]indoles. Our experimental and computational investigations suggest that dispersive interactions between the indole and styrene preorganize substrates such that 6-membered ring formation is preferred, apparently via concerted protonation and C-C bond formation. When dispersion is attenuated (by a substituent or heteroatom), regioselectivity erodes and competing oligomerization predominates for cis substrates. Similarly, all trans-configured substrates that we evaluated failed to cyclize efficiently.
Nickel-Catalyzed Arylation of C(sp3)-O Bonds in Allylic Alkyl Ethers with Organoboron Compounds
Li, Xiaowei,Li, Yuxiu,Zhang, Zhong,Shi, Xiaolin,Liu, Ruihua,Wang, Zemin,Li, Xiangqian,Shi, Dayong
supporting information, p. 6612 - 6616 (2021/09/02)
A nickel-catalyzed cross-coupling of allylic alkyl ethers with organoboron compounds through the cleavage of the inert C(sp3)-O(alkyl) bonds is described. Several types of allylic alkyl ethers can be coupled with various boronic acids or their derivatives to give the corresponding products in good to excellent yields with wide functional group tolerance and excellent regioselectivity. The gram-scale reaction and late-stage modification of biologically active compounds further prove the practicality of this synthetic method.
Br?nsted Acid-Catalyzed Intramolecular Hydroarylation of β-Benzylstyrenes
Cai, Xiao,Keshavarz, Amir,Omaque, Justin D.,Stokes, Benjamin J.
supporting information, p. 2626 - 2629 (2017/05/24)
Using triphenylmethylium tetrakis(pentafluorophenyl)borate as a convenient Br?nsted acid precatalyst, β-(α,α-dimethylbenzyl)styrenes are shown to cyclize efficiently to afford a variety of new indanes that possess a benzylic quaternary center. The geminal dimethyl-containing quaternary center is proposed to be necessary to arm the substrate for cyclization through steric biasing.
Enantiospecific, regioselective cross-coupling reactions of secondary allylic boronic esters
Chausset-Boissarie, Laetitia,Ghozati, Kazem,Labine, Emily,Chen, Jack L.-Y.,Aggarwal, Varinder K.,Crudden, Cathleen M.
, p. 17698 - 17701 (2014/01/17)
An original syn: The first enantioselective Suzuki-Miyaura cross-coupling of chiral, enantioenriched secondary allylic boronic esters is described (see scheme; DME=dimethoxyethane, Bpin = pinacolboryl, dba = dibenzylideneacetone). Mechanistic studies show that the reactions proceed via γ-selective transmetalation followed by reductive elimination. The reaction provides the first independent confirmation that the transmetalation of boronic esters proceeds via a syn pathway. Copyright
Codimerisation of styrene and α-methylstyrene in the presence of zeolites
Grigor'eva,Bubennov,Khalilov,Kutepov
experimental part, p. 85 - 90 (2012/07/13)
The reaction of styrene with α-methylstyrene has been studied over Y, Beta and ZSM-12 zeolites at 80-120 °C in the presence or absence of chlorobenzene. Homo- and codimers of styrene and α-methylstyrene were the main reaction products. The yield of dimers
The Phenyldimethylsilyl Group as a Masked Hydroxy Group
Fleming, Ian,Henning, Rolf,Parker, David C.,Plaut, Howard E.,Sanderson, Philip E. J.
, p. 317 - 338 (2007/10/02)
A phenyldimethylsilyl group attached to carbon can be converted into hydroxy group 1->5, with retention of configuration at the migrating carbon, by any of three main methods.The first involves protodesilylation, to remove the phenyl ring from the silicon atom, followed by oxidation of the resulting functionalized silicon atom using peracid or hydrogen peroxide.The second uses mercuric acetate for the same purpose, and can be combined in one pot with the oxidative step using peracetic acid.This method has a variant in which the mercuric ion is combined with palladium(II) acetate, both in less than stoichiometric amounts.The third uses bromine, which can also be used in one pot in conjuction with peracetic acid.In this method, but not in the method based on mercuric acetate, the peracetic acid may be buffered with sodium acetate.The method using bromine as the electrophile for removing the benzene ring has a more agreeable variant in which it is administered in the form of potassium bromide, which is oxidised to bromine by the peracetic acid.The scope and limitations of each of these methods are reported with a range of examples possessing between them many of the common functional groups.Simple benzene rings, alcohols, ethers, esters, amides and nitriles are compatible with all three methods, and ketones do not undergo Baeyer-Villiger reaction under any of the conditions.Amines, however, are oxidised to amine oxides.Ketones may be brominated in the third of the three main species.The absence of acid in the third method makes it especially valuable when the phenyldimethylsilyl group has a neighbouring nucleofugal group such as hydroxy or acetoxy.Carbon-carbon double bonds are incompatible with the methods, except for terminal monosubstituted double bonds, which can survive the conditions used in the first of the three methods.
The Phenyldimethylsilyl Group as a Masked Form of the Hydroxy Group
Fleming, Ian,Henning, Rolf,Plaut, Howard
, p. 29 - 31 (2007/10/02)
The phenyldimethylsilyl group can be converted in two steps, protodesilylation and peracid-mediated rearrangement, into a hydroxy group with retention of configuration: β-phenyldimethylsilyl carbonyl compounds are thus revealed to be masked aldol products.
The Preparation and Photolysis of (E)-1-Aryl-3-methyl-3-phenylbut-1-enes
Blunt, John W.,Coxon, James M.,Robinson, Ward T.,Schuyt, Helen A.
, p. 565 - 579 (2007/10/02)
Reaction of 2-methyl-2-phenylpropylmagnesium chloride with benzaldehyde in tetrahydrofuran gave, 2,7-dimethyl-2,4,5,7-tetraphenyloctane-4,5-diol as a 1:2 mixture of clear transparent crystalline plates (meso) and needles (+/-), 3-methyl-1,3-diphenylbutan-1-one, benzyl alcohol, 2-methyl-2-phenyl-propane and a low yield of 3-methyl-1,3-diphenylbutan-1-ol.The distinction between the meso- and the (+/-)-diols was unequivocal because the unique space group of the former requires the dimeric molecules to lie about a crystallographic centre of symmetry.The mechanism involved in the formation of the products of the Grignard reaction is examined.By careful choice of reaction conditions a series of 1-aryl-3-methyl-3-phenylbutan-1-ols were prepared.Dehydration of the 1-aryl-3-methyl-3-phenylbutan-1-ols with p-toluenesulfonic acid and a short reaction time gives (E)-1-aryl-3-methyl-3-phenylbut-1-enes but longer reaction times afford 3-aryl-1,1-dimethylindanes.Photolysis of the (E)-1-aryl-3-methyl-3-phenylbut-1-enes affords (Z)-1-aryl-3-methyl-3-phenylbut-1-enes and trans-1-aryl- 3,3-dimethyl-2-phenylcyclopropanes.Extended photolysis gives 4-aryl-2-methyl-3-phenylbut-1-enes via trans-1-aryl-3,3-dimethyl-2-phenylcyclopropane by rupture of the cyclopropyl bond adjacent to the aryl substituent.
