Indium Tribromide‐Catalysed Transfer‐Hydrogenation: Expanding the Scope of the Hydrogenation and of the Regiodivergent DH or HD Addition to Alkenes

Chemistry - A European Journal, Год журнала: 2021, Номер 27(43), С. 11221 - 11225

Опубликована: Май 28, 2021

Abstract The transfer‐hydrogenation as well the regioselective and regiodivergent addition of H−D from regiospecific deuterated dihydroaromatic compounds to a variety 1,1‐di‐ trisubstituted alkenes was realised with InBr 3 in dichloro(m)ethane. In comparison previously reported BF ⋅Et 2 O‐catalysed process, electron‐deficient aryl‐substituents can be applied reliably thereby several restrictions could lifted, new types substrates transformed successfully hydrodeuterogenation deuterohydrogenation reactions.

Язык: Английский

---

Aluminum‐Ligand Cooperative O−H Bond Activation Initiates Catalytic Transfer Hydrogenation

ChemCatChem, Год журнала: 2022, Номер 14(13)

Опубликована: Апрель 27, 2022

Abstract Molecular design ultimately furnishes improvements in performance over time, and this has been the case for Rh‐ Ir‐based molecular catalysts currently used transfer hydrogenation (TH) reactions fine chemical synthesis. In report, we describe a pincer ligand Al catalyst TH, (I 2 P 2− )Al(THF)Cl P=diiminopyridine; THF=tetrahydrofuran). The mechanism TH is initiated by two successive Al‐ligand cooperative bond activations of O−H bonds molecules isopropanol ( i PrOH) to afford six‐coordinate (H I P)Al(O Pr) Cl. Stoichiometric kinetic experiments suggest an ordered transition state, supported polar solvents, concerted hydride from PrO − substrate. Metal‐ligand hydrogen bonding cyclic state likely support event. available data does not involvement intermediate Al‐hydride TH. Proof‐of‐principle including conversion benzophenone acetone diphenylmethanol with 90 % 1 h are described. analogous compound, )Al(THF)H, also cleaves PrOH (HI )Al(O Pr)H , but no activity catalytic was observed.

Язык: Английский

---

Bor‐Lewis‐Säure‐katalysierte Transferhydrocyanierung α‐ und α,β‐substituierter Styrole

Angewandte Chemie, Год журнала: 2019, Номер 131(11), С. 3617 - 3621

Опубликована: Янв. 9, 2019

Abstract Ein praktikables Verfahren zur Synthese von Blausäuresurrogaten auf Basis Cyclohexa‐1,4‐dienen wurde entwickelt. Diese sind lagerbeständig, setzen aber formal HCN frei und werden rearomatisiert, wenn sie mit einer Lewis‐Säure Reaktion gebracht werden. Die Bildung des Isocyanidaddukts [(CN)BCl 3 ] − dazugehörigen Wheland‐Komplexes für BCl massenspektrometrisch bestätigt. In Gegenwart 1,1‐di‐ trisubstituierten Alkenen findet die Übertragung vom Surrogat C‐C‐Doppelbindung statt, wodurch hoch substituierte Nitrile Markownikow‐Selektivität gebildet Der Erfolg dieser Transferhydrocyanierung hängt der verwendeten ab; katalytische Mengen an (C 6 F 5 ) 2 erweisen sich als wirkungsvoll, B(C BF ⋅OEt hingegen nicht.

---

Chemoselective Hydrosilylation of the α,β-Site Double Bond in α,β- and α,β,γ,δ-Unsaturated Ketones Catalyzed by Macrosteric Borane Promoted by Hexafluoro-2-propanol

The Journal of Organic Chemistry, Год журнала: 2020, Номер 85(10), С. 6578 - 6592

Опубликована: Апрель 22, 2020

The B(C6F5)3-catalyzed chemoselective hydrosilylation of α,β- and α,β,γ,δ-unsaturated ketones into the corresponding non-symmetric in mild reaction conditions is developed. Nearly 55 substrates including those bearing reducible functional groups such as alkynyl, alkenyl, cyano, aromatic heterocycles are chemoselectively hydrosilylated good to excellent yields. Isotope-labeling studies revealed that hexafluoro-2-propanol also served a hydrogen source process.

Язык: Английский

---

Borane-catalyzed dehydrogenative C–C bond formation of indoles with N-tosylhydrazones: an experimental and computational study

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(13), С. 3428 - 3437

Опубликована: Янв. 1, 2022

A novel dehydrogenative C–C bond formation of indoles and N -tosylhydrazones to give di(indolyl)methanes (DIMs) has been demonstrated using tris(pentafluorophenyl)borane as a catalyst.

Язык: Английский

---