16503-45-0Relevant academic research and scientific papers
Enantiospecific on-water bromination: A mild and efficient protocol for the preparation of alkyl bromides
Alletto, Francesco,Adamo, Mauro F. A.
supporting information, p. 8692 - 8698 (2020/12/29)
Herein we report the first example of an on-water enantiospecific synthesis of alkyl bromides. This procedure allowed the conversion of secondary activated alkyl sulphides to benzylic alkyl bromides, which were obtained in 80-99% yields. The reaction carried out on enantio-pure sulphides provided the corresponding bromides in high yields and enantioselectivity (up to 92% ee; 94% es) at room temperature. The on-water conditions reduced significantly the reaction times compared to similar procedures run in organic media. The condition identified made use of no solvent, required no temperature control and produced a smooth organic phase easily separated for further synthetic use on a multigram-scale without the need for any organic extraction. Therefore, the present constitutes the most operationally simple and environmentally benign approach to a class of much sought organic intermediates. This journal is
Sulphide as a leaving group: Highly stereoselective bromination of alkyl phenyl sulphides
Canestrari, Daniele,Cioffi, Caterina,Biancofiore, Ilaria,Lancianesi, Stefano,Ghisu, Lorenza,Ruether, Manuel,O'Brien, John,Adamo, Mauro F.A.,Ibrahim, Hasim
, p. 9042 - 9050 (2019/10/22)
A conceptionally novel nucleophilic substitution approach to synthetically important alkyl bromides is presented. Using molecular bromine (Br2), readily available secondary benzyl and tertiary alkyl phenyl sulphides are converted into the corresponding bromides under exceptionally mild, acid- and base-free reaction conditions. This simple transformation allows the isolation of elimination sensitive benzylic β-bromo carbonyl and nitrile compounds in mostly high yields and purities. Remarkably, protic functionalities such as acids and alcohols are tolerated. Enantioenriched benzylic β-sulphido esters, readily prepared by asymmetric sulpha-Michael addition, produce the corresponding inverted bromides with high stereoselectivities, approaching complete enantiospecificity at -40 °C. Significantly, the reported benzylic β-bromo esters can be stored without racemisation for prolonged periods at -20 °C. Their synthetic potential was demonstrated by the one-pot preparation of γ-azido alcohol (S)-5 in 90% ee. NMR studies revealed an initial formation of a sulphide bromine adduct, which in turn is in equilibrium with a postulated dibromosulphurane intermediate that undergoes C-Br bond formation.
HBr–DMPU: The First Aprotic Organic Solution of Hydrogen Bromide
Li, Zhou,Ebule, Rene,Kostyo, Jessica,Hammond, Gerald B.,Xu, Bo
supporting information, p. 12739 - 12743 (2017/09/25)
HBr and DMPU (1,3-dimethyl-3,4,5,6-tetrahydro-2-pyrimidinone) form a room-temperature-stable complex that provides a mild, effective, and selective hydrobrominating reagent toward alkynes, alkenes, and allenes. HBr–DMPU could also replace other halogenating reagents in the halo-Prins reaction, ether cleavage, and deoxy-bromination reactions.
Ring-opening addition reaction of cyclopropanol derivatives with carbenes
Oku,Iwamoto,Sanada,Abe
, p. 7169 - 7172 (2007/10/02)
Chloro(phenyl)carbene and diphenylcarbene reacted with cyclopropanone hemiacetals, cyclopropanols, and cyclopropanone cyanohydrins to give 4-phenylbutanoic acid derivatives. The mechanism was explained in terms of a homolytic process that the O-H group of
SYNTHESE, EIGENSCHAFTEN UND CARBONYL-INSERTIONS-REAKTIONEN VON TETRACARBONYLEISEN(0)-KOMPLEXEN para-SUBSTITUIERTER STYROLE
Schmidt, Eckhart K.G.,Dogan, Mehmet
, p. 73 - 84 (2007/10/02)
The Fe(CO)4 η2-complexes of para-substituted styrenes (substituent=H, CH3, OCH3, Cl, F) can be obtained in good yields.Complexation changes drastically the chemical shifts and coupling constants of the vinyl protons.Reaction of the complexes wi
KETTENVERLAENGERUNG DURCH CARBONYLINSERTION BEI DER REAKTION VON (TETRACARBONYL)-(OLEFIN)EISEN(O)-KOMPLEXEN MIT OXIDATIONSMITTELN
Schmidt, E. K. G.,Wiese, W.
, p. 4425 - 4428 (2007/10/02)
On oxidation of (tetracarbonyl)(olefin)iron(O)-complexes in alcoholic solvents esters carrying a substituent in the 3-position are formed by a carbonylinsertion reaction.
