1613378-06-5Relevant academic research and scientific papers
Synthesis of indoles by domino reaction of 2-(tosylamino)benzyl alcohols with furfurylamines: Two opposite reactivity modes of the α-carbon of the furan ring in one process
Uchuskin, Maxim G.,Molodtsova, Natalia V.,Lysenko, Sergey A.,Strel'Nikov, Vladimir N.,Trushkov, Igor V.,Butin, Alexander V.
, p. 2508 - 2515 (2014/05/06)
An unusual domino reaction where the same furan α-carbon atom reacts initially as a nucleophile and then as an electrophile is reported. In the presence of acid, N-tosylfurfurylamines react with 2-(tosylamino)benzyl alcohols to afford 2-(2-acylvinyl)indoles. The reaction proceeds by Friedel-Crafts alkylation at the C(2) atom of furan followed by acid-catalyzed intramolecular nucleophilic attack of the ortho-amino group onto the same carbon atom. The replacement of the tosylamino leaving group by phthalimide enables generation of a different type of indole yet allows the ambiphilic nature of C(2) to be retained. Both types of indoles were obtained when N-furfurylbenzamides were employed. Furfurylamines react with 2-(tosylamino)benzyl alcohols affording 2-(2-acylvinyl)indoles by a domino reaction sequence in which the same furan α-carbon atom behaves initially as an electron-rich center and then as an electron deficient one. In addition, substitution of the tosylamino leaving group with a phthalimido group furnishes a change in chemoselectivity. Copyright
