Construction of a Cyclic Skeleton

 

1) Intramolecular Cyclization

2) Intermolecular Annulation

Facile and efficient construction of a heterocyclic skeleton by Intramolecular cyclization in the presence of a metal catalyst and a promoter

1) Indium bromide efficiently catalyzed intramolecular cyclization of ethynylanilines, which contained either N-unsubstituted or N-substituted amino group, producing indole skeletons.

Tetrahedron Lett. 2006, 47, 631.

J. Org. Chem. 2008, 73, 4160.

1) Indium bromide promoted dimerization of two molecules of ethynyl anilines, which had a trimethylsilyl acetylene or had no substituent group on the terminal carbon, producing quinolines skeletons.

Facile construction of a heterocyclic skeleton by Intermolecular annulation or incorporation of a carbon source with a skeleton precursor in the presence of a metal catalyst and a promoter.

  1. J. Org. Chem. 2006, 71, 3653.

  2. J. Org. Chem. 2008, 73, 4160.

3) Copper triflate smoothly catalyzed the coupling of anilines with propargylic acetates in the presence of Me3SiCl as a promoter leading to the production of 2,3-disubstituted indole derivatives. This annulation proceeds through the following three steps; i) substitution, ii) aza-Claisen rearrangement, iii) cyclization.

2) Divergent reductive synthesis between lactam derivatives and nitrogen containing-heterocycles from primary amines and keto acids could be achieved by switching of the indium compound.

Tetrahedron. Lett. 2016, 57, 2175.

2) Trimethylchlorosilane (Me3SiCl) catalyzed intramolecular cyclization of N,O-acetals, producing benzodiazepine skeletons.

ジアゼパム

(抗不安薬、睡眠薬)

我々が開発した方法では、ジアゼパムやジプレキサ(抗精神病薬)などを合成するために必要な医薬中間体であるベンゾジアゼピン骨格を1段階で合成することが可能です。

Tetrahedron 2010, 66, 6837.

Org. Lett. 2012, 14, 836.

Eur. J. Org. Chem. 2015, 1905.

4) Copper(II) halide effiently catalyzed the intermolecular annulation of either ethynylanilines or propargylic amines with N,O-acetals, which functioned as a C1 unit, producing quinoline or pyrrole derivatives.

キヌレン酸

（抗興奮作用）

CuX2触媒が、適切なアルキンアミンとの環化反応を促進して、キノリン環やピロール環が一段階で合成できることを新たに見出しました。N,O-アセタールが、環骨格のC1ユニットとして機能することも明らかにしました。

キノリン環

Facile Construction of a Cyclic Skeleton

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Angew. Chem. Int. Ed. 2016, 55, 1864.

ピロール環

インドール骨格

キノリン環

ラクタム環

>>

3) Palladium-catalyzed intramolecular cyclization of aromatic carboxylic acids tethered with an alkyne moiety, producing vinyl dioxanone derivatives having a quaternary allylic carbon through a novel cyclization manner.

Org. Lett. 2017, 19, 5296.

4) Gallium-catalyzed reductive intramolecular cyclization of γ-keto acids in the presence of a hydrosilane, leading to the preparation of γ-lactones.

RSC Adv. 2016, 6, 81763.