Open AccessDearomative Indole (3 + 2) Reactions with Azaoxyallyl Cations – New Method for the Synthesis of Pyrroloindolines
Author(s) -
Maria C. DiPoto,
Russell P. Hughes,
Jimmy Wu
Publication year - 2015
Publication title -
journal of the american chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.115
H-Index - 612
eISSN - 1520-5126
pISSN - 0002-7863
DOI - 10.1021/jacs.5b10221
Subject(s) - chemistry , indole test , annulation , density functional theory , ring (chemistry) , solvent , computational chemistry , transition state , stepwise reaction , closure (psychology) , combinatorial chemistry , catalysis , stereochemistry , organic chemistry , order of reaction , kinetics , reaction rate constant , market economy , physics , quantum mechanics , economics
Herein, we report the first examples of the synthesis of pyrroloindolines by means of (3 + 2) dearomative annulation reactions between 3-substituted indoles and highly reactive azaoxyallyl cations. Computational studies using density functional theory (DFT) (B3LYP-D3/6-311G**++) support a stepwise reaction pathway in which initial C-C bond formation takes place at C3 of indole, followed by ring closure to give the observed products. Insights gleaned from these calculations indicate that the solvent, either TFE or HFIP, can stabilize the transition state through H-bonding interactions with oxygen of the azaoxyallyl cation and other relevant intermediates, thereby increasing the rates of these reactions.