Diels-Alder [4+2] Reaction ディールス・アルダー反応

Outline

Publication-2 Update
Chem. Rec., 19(1), 77-84. https://doi.org/10.1002/tcr.201800048
“Rapid Optimization of Reaction Conditions Based on Comprehensive Reaction Analysis Using a Continuous Flow Microwave Reactor”
Péter Vámosi  Keiya Matsuo  Tsuguya Masuda  Dr. Kohei Sato  Dr. Tetsuo Narumi Dr. Kazuhiro Takeda  Dr. Nobuyuki Mase
Abstract
  Generally, the flow method has the advantage of a precise control over the reaction parameters and a facile modification of the reaction conditions, while a continuous flow microwave reactor allows for the quick optimization of reaction conditions owing to the rapid uniform heating. In this study, we developed a “9+4+1 method” to optimize reaction conditions based on comprehensive reaction analysis using a flow microwave reactor. The proposed method is expected to contribute to the synthesis of various fine and bulk chemicals by reducing cost and wastage, and by conserving time.
Equipment information Reactor size: 200 mm, Maximum power: 200 W (SAIDA FDS INC.)

Publication-1
(Paper) RSC Adv., 2015, 5, 10204-10210, DOI: 10.1039/C4RA12428F 
“Development of a highly efficient single-mode microwave applicator with a resonant cavity and its application to continuous flow syntheses”
Saori Yokozawaa, Noriyuki Ohnedaa, Ken Muramatsua, Tadashi Okamotoa, Hiromichi Odajimaa, Takashi Ikawab, Jun-ichi Sugiyamac, Masashi Fujitad, Taira Sawairid, Hiromichi Egamid, Yoshitaka Hamashimad, Masahiro Egid and Shuji Akai

Abstract
  Microwave-assisted organic synthesis has many advantages and is widely applied to a variety of reactions. We have developed a new single-mode microwave applicator, specific to continuous flow synthesis, whose main feature is that it generates a uniform electromagnetic field inside its resonant cavity. Two well-known reactions, the Fischer indole synthesis and the Diels–Alder reaction, proceeded very quickly when a solution of substrates was pumped through a helical glass tube reactor inside the resonant cavity, under a pressure of 2.5 MPa. The desired products were obtained in high yields. This compact apparatus constitutes a new method for switching organic synthesis from batch to continuous flow, and enables continuous synthesis of products at a scale of 100 g h−1 or more.
Equipment information Reactor size: 200 mm, Maximum power: 200 W (SAIDA FDS INC.)

概要

論文概要１ (RSC Adv., 2015, 5, 10204-10210.)

実験方法１
　① ジエチルアセチレンジカルボキシレート（1.1 M）とフラン（4.4 M）をn-PrOHと混合した。

　② ポンプにより試液をマイクロ波照射装置（200W機）に5.0 mL/minの流速で送液した（2.5 MPa）。

　③ マイクロ波を照射し（60 W）、約5分後、温度が一定になったことを確認し（194 °C）、反応液を5分間採取した。

　④ 採取した反応液を濃縮し、シリカゲルカラムクロマトグラフィにて精製し（n-hexane/EtOAc = 10/1）、生成物を4.91 g得た（76%）。

実験結果提供：静岡県立大学　江上寛通先生、赤井周司先生、濱島義隆先生
装置情報：200 mmキャビティ、200 W