Enantioselective synthesis of almorexant via iridium-catalysed intramolecular allylic amidation

Easy Entry into Reduced Ar‐BIANH2 Compounds: A New Class of Quinone/Hydroquinone‐Type Redox‐Active Couples with an Easily Tunable Potential

“…Compounds of the family bis(aryl)acenaphthenequinonediimine (Ar‐BIAN) ( 1 ; see Scheme ) have been known for some time,1–3 but have been brought to the general attention only in the 90s by Elsevier and his group 4. Since then, they have found widespread use mostly as ligands for transition metals and the corresponding complexes have been employed as catalysts for a wide variety of reactions, such as alkene hydrogenation,5 polymerization,6–11 copolymerization,12–18 aziridination,19 cyclopropanation,19 and epoxidation20 alkene‐CO copolymerization,21–24 alkyne coupling in the presence of halogens or organic halides and tin compounds25–27 or just tin compounds,28 selective semihydrogenation of alkynes29 and allenes,30 allylic aminations of olefins by nitroarenes in the presence of CO,31–33 the synthesis of pyrroles and oxazines from dienes, nitroarenes and CO,34 the reduction of nitroarenes to anilines by CO/H 2 O,35–37 the hydroamination of alkynes,38 the homo‐coupling of organic halides39 and their cross‐coupling reaction with organomagnesium, ‐zinc, and ‐tin reagents,40–44 the Suzuki–Miyaura cross coupling,45 the synthesis of 4‐quinolones and 2,3‐dihydroquinolones from 2′‐nitrochalcones and CO,46, 47 the synthesis of indoles from o ‐nitrostyrenes and CO,47, 48 the Heck arylation of olefins,49, 50 and oxidative Heck reaction,51, 52 the synthesis of dihydrofurans and dihydrobenzoxepines53 and N ‐acyl vinilogous carbamic acids,54 the cyclotrimerization of alkynes,55 the click reaction,56 the dimerization of vinyl ethers to acetals,57 and the diboration of α,β‐unsaturated carbonyl compounds 58. For some of these syntheses, the use of the Ar‐BIAN ligands was instrumental in achieving a high performance of the catalytic system.…”

Novel strategies for catalytic asymmetric synthesis of C1-chiral 1,2,3,4-tetrahydroisoquinolines and 3,4-dihydrotetrahydroisoquinolines

“…44 Using this methodology the same group completed a straightforward four step total synthesis of the natural product almorexant. 45 2.4.2 Asymmetric intramolecular aza-Michael addition reaction. The asymmetric intramolecular aza-Michael addition reaction constitutes another important de novo synthetic approach toward construction of important nitrogen containing heterocycles, including C1-chiral THIQs.…”

Comprehensive Strategies for the Synthesis of Isoquinolines: Progress Since 2008

“…The synthetic route goes through iridium catalyzed conversion of 3,4-dimethoxyphenethylamine into allylic carbonate which is followed by cyclisation to give the tetrahydroisoquinoline derivative (Scheme 97). [117] Liu et al have reported the Ir(III)-catalyzed CÀ H activation followed by annulation of benzimidates 86 with hydroxylisopropylalkynes 57 to obtain isoquinolines 186. [118] The present method rely on the same strategy followed by Anukumar et al [119] as both the groups have used the same kind of substrates while catalyst being different, latter used Ru-catalyst.…”

“…The synthetic route goes through iridium catalyzed conversion of 3,4‐dimethoxyphenethylamine into allylic carbonate which is followed by cyclisation to give the tetrahydroisoquinoline derivative (Scheme 97). [117] …”