Synthesis and Evaluation of Antimicrobial Activities of Novel N-Substituted Indole Derivatives

Table 1

Optimization of O-alkylation reaction^a.

Entry	Base (mol%)	Additives (equiv.)	Solvent (mL)	Temperature (°C)	Yield of 1^b,c (%)
1	KOH	—	Neat	25	Traces
2	Pyridine	—	Pyridine	80	nr
3	K2CO3	—	CH3CN	80	25
4	K2CO3	—	DMF	100	20
5	K2CO3 (50)	TBAF	DMF	80	35
6	K2CO3 (50)	TBAF (1)	CH3CN	50	50
7	K2CO3 (100)	TBAF (1)	CH3CN	50	72^d

^aReaction conditions: alcohol (1.5 mmol), indole-alkyl bromide (1 mmol), base, and solvent; ^bisolated yield; ^ccharacterized by IR and NMR; ^dfurther yield did not improve even when the 1.5 equiv. of base was utilized.