Table 2. Effect of Mode of Addition on the Outcome of the Alkylation Reaction^a.

entry	mode of addition	HPLC IPC (area % at 245 nm)b
		SM	product	impurity
1	all reagents added at room temp. and heated to 80 °C	10	79	11
2	dropwise addition of a solution of aniline in sulfolane to the hot reaction mixture	13	78	9
3	dropwise addition of 50 wt % NaOH (aq) to the hot reaction mixture	3	86	8
4	dropwise addition of a solution of bromo-oxetane in sulfolane to the hot reaction mixture	10	77	12
5	separate dropwise addition of both aq NaOH and aniline solution to the hot reaction mixture	3	90	5
6	dropwise addition of a solution of aniline and bromo-oxetane in sulfolane to the hot reaction mixture	4	92	2

^aGeneral reaction conditions: aniline (2, 1.0 g, 1 equiv), BBMO (3, 1.2 equiv), NaOH (2.5 equiv), and sulfolane (10 mL) were added together as described in the table. The temperature was 80 °C for all reaction, and the overall reaction time was 3 h. In the cases where two sulfolane solutions were added together, half of the solvent was used to make each individual solution so that the final reaction volume would remain fixed.

^bThese percentages are not adjusted for response factors.