Copper‐Catalyzed Domino S_N2′/Coupling Reaction: A Versatile and Facile Synthesis of Cyclic Compounds from Baylis–Hillman Acetates

Abstract

A variety of substituted quinoline/pyridine, thiochromene and naphthalene derivatives, which might be of biological and medicinal value, were synthesized by copper-catalyzed domino S N 2'/coupling, S N 2'/deacylation/coupling and S N 2'/coupling/elimination reactions. The method provides a general and convenient approach to the synthesis of various sub-stituted cyclic compounds from the corresponding Baylis-Hillman (B-H) acetates and N-/S-/C-nucleophiles.

Cascade SN2′–SNAr, Elimination, and 1,5‐Hydride Shift Reactions by Acetylacetone/Acetoacetic Esters: Synthesis of 9,10‐Dihydroacridines

“…We began our studies with MBH acetate 1a by using our previously reported conditions (Scheme ). [6b] Initially, reaction of 1a (0.5 mmol) with methyl acetoacetate (1.5 equiv.) was performed by using K 2 CO 3 (1.5 equiv.)…”

“…They are highly versatile reagents in synthetic organic chemistry because of their easy conversion into the corresponding enolates They have been employed in a variety of reactions such as condensation, alkylation, cyclization halogenation, acylation, and Michael addition . Recently, their cascade reaction with Morita–Baylis–Hillman (MBH) acetates through successive S N 2′–S N Ar and eliminative aromatization was reported for the synthesis of naphthalene and quinoline derivatives (Figure ) . We also reported the synthesis of acridine[6b] by using malononitrile.…”

“…Recently, their cascade reaction with Morita–Baylis–Hillman (MBH) acetates through successive S N 2′–S N Ar and eliminative aromatization was reported for the synthesis of naphthalene and quinoline derivatives (Figure ) . We also reported the synthesis of acridine[6b] by using malononitrile.…”

“…However, the use of active methylene compounds containing an acetyl group remains elusive. [6a], [6d] It can be speculated that cascade reactions of these reagents with MBH acetates should also lead to fused aromatic derivatives. Our expedition for the application of acetyl acetone with MBH acetate lead to the discovery of a method for the metal‐free synthesis of 9,10‐dihydroacridines from 2‐chloroquinolinyl‐3‐carbaldehyde[7d] derived MBH acetates .…”

A practical Cu(I)-catalyzed domino approach to 1,2-disubstituted indoles and its application for the assembly of indolophenanthridines

“…Furthermore, a one-pot approach to indolo[1,2-f]-phenanthridines from o-alkynylanilines and 1,2-dihaloarenes has not been achieved until now. As part of our ongoing research efforts toward the domino synthesis of heterocycles under copper catalysis, 27,[37][38][39][40] we became interested in applying the one-pot protocol to the assembly of 1,2-disubstituted indoles and the tandem synthesis of indolo[1,2-f]phenanthridines. The findings are reported herein.…”