Synthesis of bis(indolyl)methanes under catalyst-free and solvent-free conditions

Figures & data

short-legendScheme 1. Probable mechanism for the formation of bis(indolyl)methanes.

Table 1. Synthesis of bis(indolyl)methanes

				Method 1		Method 2
Entry	R^1	R	Product	Reaction time	Yields^a (%)	Reaction time	Yields^a (%)
A	4-NO2C6H4	H	3a	6 days	58	8 h	60
B	2-NO2C6H4	H	3b	18 h	61	6 h	61
C	4-ClC6H4	H	3c	5 days	92	23 h	95
D	2-ClC6H4	H	3d	45 min	96	15 min	96
E	C6H5	H	3e	48 h	61	2 h	86
F	3-MeOC6H4	H	3f	5 days	57	13 h	86
G	2-furyl	H	3g	24 h	62	90 min	87
H	2-pyridyl	H	3h	13 h	59	10 h	94
I	4-NO2C6H4	Me	3i	7 h	51	105 min	60
J	4-ClC6H4	Me	3j	3 h	77	100 min	97
K	2-ClC6H4	Me	3k	3 min	97	2 min	98
L	C6H5	Me	3l	3 days	69	7 min	90
M	3-MeOC6H4	Me	3m	3 days	63	2 h	87
N	2-furyl	Me	3n	10 min	77	5 min	85
O	4-MeOC6H4	Me	3o	5 days	53	2 days	83
P	2-pyridyl	Me	3p	7 h	63	15 min	96
^aYield of isolated product.

Table

Table of contents:
General information	2
General Procedure for the formation of bis(indolyl)methane	2
Characterisation data for compounds	2
Copy of ^1H NMR and ^13C NMR spectra of compounds	7
HRMS and LC-MS of selected compounds	40