Palladium-Catalyzed, Modular Synthesis of Highly Functionalized Indoles and Tryptophans by Direct Annulation of Substituted <i>o</i>-Haloanilines and Aldehydes
作者:Yanxing Jia、Jieping Zhu
DOI:10.1021/jo061471s
日期:2006.9.1
One-pot synthesis of indoles by a palladium-catalyzed annulation of ortho-haloanilines and aldehydes has been developed. Coupling of ortho-iodoaniline with aldehyde is realized under mild ligandless conditions [Pd(OAc)2, DABCO, DMF, 85 °C], whereas X-Phos is found to be the ligand of choice for coupling reactions involving ortho-chloroanilines/ortho-bromoanilines and aldehydes. A variety of ortho-haloanilines
Compounds having the structural formula ##STR1## where X, Y, R and Z are defined in the specification are disclosed. The compounds of this invention are effective for controlling mites, nematodes, rice planthopper, tobacco budworm, and southern corn rootworm. Methods for making these compounds are also set forth.
Ugi-Post Functionalization, from a Single Set of Ugi-Adducts to Two Distinct Heterocycles by Microwave-Assisted Palladium-Catalyzed Cyclizations: Tuning the Reaction Pathways by Ligand Switch
作者:William Erb、Luc Neuville、Jieping Zhu
DOI:10.1021/jo900210x
日期:2009.4.17
Linear amides 4, prepared in one step by the Ugi four-component reaction, were converted to 3,4-dihydroquinoxalin-3-ones (5) or to 2-(2-oxoindolin-1-yl)acetamides (6) dependent on the catalytic conditions. While microwave irradiation was found to be determinant on the reaction efficiency, the choice of ligand diverged the reaction pathways. Heating a solution of 4 in dioxane/MeCN (v/v = 85/ 15) under microwave irradiation conditions in the presence of Pd(dba)(2) (0.05 equiv) and CS2CO3 (2 equiv), using XPhos as a supporting ligand, afforded the 3,4-dihydroquinoxalin-3-ones (5) via an intramolecular N-arylation of the secondary amide. On the other hand, using BINAP as ligand under otherwise identical conditions, intramolecular alpha-CH arylation of tertiary amide occurred to furnish the oxindoles (6).