89291-23-6Relevant articles and documents
Practical and Scalable Synthesis of Borylated Heterocycles Using Bench-Stable Precursors of Metal-Free Lewis Pair Catalysts
Jayaraman, Arumugam,Misal Castro, Luis C.,Fontaine, Frédéric-Georges
supporting information, p. 1489 - 1499 (2018/10/26)
A practical and scalable metal-free catalytic method for the borylation and borylative dearomatization of heteroarenes has been developed. This synthetic method uses inexpensive and conveniently synthesizable bench-stable precatalysts of the form 1-NHR2-2-BF3-C6H4, commercially and synthetically accessible heteroarenes as substrates, and pinacolborane as the borylation reagent. The preparation of several borylated heterocycles on 2 and 50 g scales was achieved under solvent-free conditions without the use of Schlenk techniques or a glovebox. A kilogram-scale borylation of one of the heteroarene substrates was also achieved using this cost-effective green methodology to exemplify the fact that our methodology can be conveniently implemented in fine chemical industries.
Asymmetric Cycloisomerization of o-Alkenyl-N-Methylanilines to Indolines by Iridium-Catalyzed C(sp3)?H Addition to Carbon–Carbon Double Bonds
Torigoe, Takeru,Ohmura, Toshimichi,Suginome, Michinori
supporting information, p. 14272 - 14276 (2017/10/23)
Highly enantioselective cycloisomerization of N-methylanilines, bearing o-alkenyl groups, into indolines is established. An iridium catalyst bearing a bidentate chiral diphosphine effectively promotes the intramolecular addition of the C(sp3)?H bond across a carbon–carbon double bond in a highly enantioselective fashion. The reaction gives indolines bearing a quaternary stereogenic carbon center at the 3-position. The reaction mechanism involves rate-determining oxidative addition of the N-methyl C?H bond, followed by intramolecular carboiridation and subsequent reductive elimination.
Novel extensions of the tert-amino effect: Formation of phenanthridines and diarene-fused azocines from ortho-ortho′-functionalized biaryls
Polonka-Bálint, ágnes,Saraceno, Caterina,Ludányi, Krisztina,Bényei, Attila,Mátyus, Péter
scheme or table, p. 2846 - 2850 (2009/05/07)
Phenanthridines and azocines fused to two benzene rings or one benzene and one pyridazinone ring, which are otherwise difficult to access, were prepared via two new extensions of the tert-amino effect. The synthetic pathway includes three steps: i) Suzuki reaction of an ortho-functionalized phenylboronic acid with ortho-disubstituted benzenes or pyridazinones; ii) the Knoevenagel condensation reaction of the biaryl aldehydes formed with active methylene compounds to obtain vinyl derivatives or, through their cyclization, phenanthridines via a tert-amino effect; and iii) thermal isomerization of vinyl or phenanthridinium compounds to fused azocines via another type of tert-amino effect. Georg Thieme Verlag Stuttgart.
