One-Pot Synthesis of 2,4-Disubstituted Indoles fromN-Tosyl-2,3-dichloroaniline Using Palladium–Dihydroxyterphenylphosphine Catalyst
摘要:
4-Chloroindoles were synthesized from readily available 2,3-dichloroaniline derivatives and terminal alkynes. The catalyst composed of palladium and dicyclohexyl(dihydroxyterphenyl)phosphine (Cy-DHTP) enabled ortho-selective Sonogashira coupling, and subsequent cyclization afforded 4-chloroindoles in high yields. This transformation was successfully applied to the one-pot synthesis of 2,4-disubstituted indoles via Suzuki-Miyaura coupling after indole formation.
One-Pot Synthesis of Substituted Benzo[<i>b</i>]furans and Indoles from Dichlorophenols/Dichloroanilines Using a Palladium–Dihydroxyterphenylphosphine Catalyst
Sonogashira coupling of dichlorophenols and terminal alkynes, followed by cyclization and Suzuki–Miyauracoupling in one pot, using a palladium–dihydroxyterphenylphosphine (Cy-DHTP) catalyst. The use of substoichiometric amounts of tetrabutylammonium chloride was effective in accelerating the Suzuki–Miyauracoupling. This protocol was also successfully applied to the one-pot synthesis of disubstituted
二取代的苯并[ b ]呋喃是通过二氯苯酚和末端炔的邻位选择性Sonogashira偶联反应,然后使用钯-二羟基叔苯基膦(Cy-DHTP)催化剂在一个罐中进行环化和Suzuki-Miyaura偶联反应而合成的。亚化学计量的四丁基氯化铵的使用有效地加速了Suzuki-Miyaura偶联。该方案也成功地用于从二氯苯胺衍生物的一锅法合成二取代的吲哚。