13154-12-6Relevant articles and documents
Vinylic Organoboranes. 13. A Convenient Stereospecific Synthesis of (Z)-1-Halo-1-alkenes from 1-Alkynes via (E)-1-Alkenylborane Derivatives with Halogens
Brown, Herbert C.,Subrahmanyam, Chitti,Hamaoka, Tsutomu,Ravindran, Nair,Bowman, Donald H.,et al.
, p. 6068 - 6075 (1989)
The reaction of (E)-1-alkenylborane derivatives with bromine under various conditions was investigated, and a simple stereospecific synthesis of (Z)-1-bromo-1-alkenes has been developed.Addition of bromine to (E)-1-alkenyldisiamylborane, derived from the
13C NMR Spectra of the Products of Hydroboration of 1-Alkynes and of 1-Halo-1-alkynes with 9-Borabicyclononane and with Dicyclohexylborane. Investigation of the Thermal Decomposition of Some (1-Halo-1-alkenyl)dicyclohexylboranes
Blue, Clarence D.,Nelson, Donna J.
, p. 4538 - 4542 (1983)
13C NMR spectra were obtained (1) of alkenylboranes and 1,1-diboraalkanes, the products of mono- and dihydroboration of 1-alkynes, respectively, and (2) of (1-halo-1-alkenyl)dialkylboranes, the products of hydroboration of 1-halo-1-alkynes with the title compounds.The chemical shift for C-1 of each 1,1-diboraalkane is reported.The products of the reactions of 9-borabicyclononane with 1-halo-1-alkynes show upfield shifts (ca. 10 ppm) for the alkene C-2 upon changing the solvent from CDCl3 to THF.This indicates formation of an organoborane-THF complex, which is cited as the reason for slower protonolysis in THF solvent.The corresponding dicyclohexylborane products show much smaller 13C shifts and undergo protonolysis rapidly in either CDCl3 or THF solvent.With the dicyclohexylborane products, a cyclohexyl group migrates slowly at room temperature to give, after AcOH protonolysis, the 1-cyclohexyl-1-alkene.
Practical regio- and stereoselective azidation and amination of terminal alkenes
Ojo, Olatunji S.,Miranda, Octavio,Baumgardner, Kyle C.,Bugarin, Alejandro
, p. 9354 - 9358 (2019/01/03)
There is significant interest in developing more rapid and efficient production of nitrogen-containing allylic compounds, as widely used in various syntheses. This work reports a variety of allylic azides and allylic amines synthesized by an efficient, new one-pot protocol that employs readily available terminal alkenes as starting materials. This method is highly regio- and stereoselective, affording the linear (E)-isomer, under metal-free conditions. This process tolerates several functional groups including halogen-containing molecules; it is general for azides and amine nucleophiles; and, adducts were obtained in good yields.
One-pot synthesis of telluroketene acetals and haloketene acetals using sp2 geminated hetero organobismetallic intermediates
Guerrero Jr., Palimécio G.,De Oliveira, Paulo R.,Baroni, Adriano C.M.,Marques, Francisco A.,Labes, Ricardo,Dabdoub, Miguel J.
experimental part, p. 1582 - 1586 (2012/04/10)
A novel one-pot synthesis of 1,1-dihalo-1-alkenes and 1,1-bis(butyltelluro) -1-alkenes was developed from hydrozirconation of alkynylzinc bromide with Cp2Zr(H)Cl and subsequent capture of the Zn/Zr 1,1-heterodimetallo-1- alkene intermediates wi
Reactions of fluoroalk-1-en-1-yltrifluoroborate and perfluoroalk-1-yn-1- yltrifluoroborate salts and selected hydrocarbon analogues with hydrogen fluoride and with halogenating agents in aHF and in basic solvents
Bardin, Vadim V.,Adonin, Nicolay Yu.,Frohn, Hermann-Josef
experimental part, p. 114 - 128 (2012/04/10)
The relative rate of the electrophilic hydrodeboration of K[R′BF 3] with HF (27-100%) diminishes in the series R′ = C 4H9CC > C4F9CFCFCC > CF 2C(CF3) > C3F7CC ～ (CF 3)2CFCC > CF3CC. When R′ = CF 3CC the new salt K[CF3CH2-CF2BF 3] was obtained by addition of HF besides CF3CCH and K[BF4]. Small amounts of water caused the formation of K[CF 3CH2-C(O)BF3] as a by-product. The electrophilic halofluorination of perfluoroalkenyltrifluoroborate salts with NCS or NBS in aHF (anhydrous HF) led to K[RFCFHal-CF2BF 3] (from K[RFCFCFBF3]) and K[R FCHal2-CF2BF3] (from K[R FCHalCFBF3] and K[RFCCBF3]) (Hal = Cl, Br). Treatment of K[RFCFCFBF3] and K[R FCCBF3] with 5% F2/N2 in MeCN gave the corresponding salts K[RFCF2-CF2BF 3] in 16-25% isolated yield. Reactions of K[trans-C4F 9CFCFBF3] with Cl2 in MeOH resulted in K[C 4F9CFCl-C(O)BF3] (major product). The latter was also obtained in reactions of K[trans-C4F9CFCFBF 3] with Cl2 in MeCN or sulfolane after sequential methanolysis of the primarily formed products. In contrast, the salts K[RCFCFBF3] (R = CnF2n+1, trans-C 4H9) and K[CF3CCBF3] underwent bromodeboration to RCFCFBr and CF3CCBr, respectively, when they were reacted with bromine in the polar solvents MeOH, MeCN, or sulfolane.
One-pot synthesis of substituted styrenes from vicinal dibromoalkanes and arylboronic acids
Tikhonov,Vasil'ev,Chirskaya,Struchkova,Merkulova,Zlotin
, p. 122 - 129 (2008/02/08)
Dehydrobromination of vicinal dibromoalkanes in systems comprising 1,2-dimethoxy-ethane, N-butyl-N′-methylimidazolium tetrafluoroborate (or tetrabutylammonium bromide), and a base with subsequent palladium-catalyzed cross-coupling of the thus formed bromoalkenes with arylboronic acids furnished substituted styrenes. Springer Science+Business Media, Inc. 2007.
A convenient preparation of mono- or gem-di-halogenoalkanes from α-sulfonyl carbanions and halogenolithiocarbenoids.
Charreau, Philippe,Julia, Marc,Verpeaux, Jean-Noel
, p. 201 - 210 (2007/10/02)
Various α-sulfonyl carbanions have been shown to react at low temperature with di- or tri-halogenolithiocarbenoids, to give 1-mono- or 1,1-di-halogenoalkanes.Bromocarbenoids gave better results than their chloro-analogues.Reaction of dibromolithiomethane with α-lithiated sulfones gives a high yield of vinylic bromides, the stereochemistry of which is cleanly E.Evidence is presented that the carbenoid itself is responsible for the reaction, and is not first converted into the corresponding carbene.
AN EFFICIENT METHOD FOR PREPARATION OF TRIMETHYLSILYL ETHYLENE OXIDE AND SOME OTHER TRIMETHYLSILYL OXIRANES
Jankowski, P.,Masnyk, M.,Wicha, J.
, p. 873 - 880 (2007/10/02)
Trimethylsilyl ethylene oxide and other α,β-epoxysilanes were obtained from corresponding (trimethylsilyl)alkenes by an one-pot procedure involving successive treatment with N-bromosuccinimide and aqueous sodium hydroxide.
Application of Phase Transfer Catalysis, 14.- Preparation of Alkynes from Halides with Solid Potassium tert-Butoxide and Crown Ether
Dehmlow, Eckehard V.,Lissel, Manfred
, p. 1 - 13 (2007/10/02)
Preparatively very simple and mild HX eliminations with solid potassium tert-butoxide in petroleum ether in the presence of catalytic amounts of crown-6 are described. 1,2-Dihalides (from alkenes) and 1,1-dihalides (from aldehydes) yield 1-alkynes; internal geminal dihalides (from symmetric ketones) give internal alkynes in excellent yields. 2,2-Dihalides (from methyl ketones) yield homogeneous 1-alkynes only if the 3-position is blocked. (E)-Haloalkenes lead also to alkynes in a syn-elimination process.
