Pd-Catalyzed Dearomative Asymmetric Allylic Alkylation of Naphthols with Alkoxyallenes

Abstract

A Pd-catalyzed linear selective intermolecular asymmetric dearomative allylic alkylation reaction of naphthols with alkoxyallenes under mild reaction conditions is reported. The transformation is successfully promoted by Pd2(dba)3 and the chiral Trost ligand and provides a general atom-efficient protocol to obtain various β-naphthalenones bearing an all carbon quaternary stereogenic center in good yields and chemo- and stereoselectivities.

Iridium Catalysed Asymmetric Allylic Substitution Reaction of Indolizine Derivatives

“…Reaction condition optimization. [a] Entry 2 Additive Solvent Yield [%] [b] ee [%] [c] 1 2 a (entries [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. The reaction generated product 3 g-3 t in overall excellent enantioselectivities (95-> 99% ee) and good yields (68-96%).…”

“…(m, 4H), 6.76 (td, J = 6.9, 1.3 Hz, 1H), 6.47-6.38 (m, 1H), 5.65 (d, J = 6.5 Hz, 1H), 5.37 (dt, J = 10.2, 1.3 Hz, 1H), 5.11 (dt, J = 17.1, 1.4 Hz, 1H), 4.34 (qd, J = 7.2, 1.9 Hz, 2H), 1.35 (t, J = 7.2 Hz, 3H). 13 19 F NMR (471 MHz, CDCl 3 ) δ À 73.0. > 99% ee as determined by HPLC (Chiralcel AD-H, 90 : 10 hexanes/i-PrOH, 1 mL/min), tr (major) = 6.23 min, tr (minor) = 5.60 min.…”

“…[18] Because indolizines is nucleophilic, we envisioned that the indolizine derivative could act as a nucleophile to react with the electrophilic p-allyl-Ir intermediate generated from an iridium catalyst and allylic alcohol derivative. In continuation of our research interests in AAS reactions, [19] herein we report a iridium/P,olefin (Carreira ligand) catalysed AAS reaction of indolizines with allylic alcohols to afford enantiomeric enriched 3-allyl indolizine derivatives. [20]…”

Metal-Catalyzed Intermolecular Hydrofunctionalization of Allenes: Easy Access to Allylic Structures via the Selective Formation of C–N, C–C, and C–O Bonds

“…103 A similar de-aromatization of naphthol with mono-substituted alkoxyallenes has been reported by the group of Zeng. 104 In 2018, under gold-silver co-catalysis, Lee and co-workers extended the hydroarylation of enantioenriched 1,3 disubstituted allenes with indoles derivatives with high chirality transfer (Scheme 43). 105 High enantioselectivity was achieved and use of highly nucleophilic (hetero)aryl favoured hydroarylation rather than racemization, contributing to the efficient chirality transfer.…”

Synthesis of C5-Allylindoles through an Iridium-Catalyzed Asymmetric Allylic Substitution/Oxidation Reaction Sequence of N-Alkyl Indolines

“…Aniline, which is always used as a nucleophile to react with electrophiles due to its high electron density at the para position, was successfully applied in the AAS reaction by Fu’s research group (Scheme b) . As a continuation of our research interest in AAS reactions, herein we report the highly stereoselective synthesis of C5-allylindoles through an iridium-catalyzed AAS reaction of N -alkyl indolines with allylic alcohols followed by an oxidation reaction in a one-pot reaction (Scheme c). This method tolerates a broad range of indolines and 1,2,3,4-tetrahydroquinoline analogues with various functional groups.…”