Scope of the coupling conditions optimised by factorial design. Conditions: 2 (5 nmol), amine (0.5 M), 2,6-lutidine (1.5 M), DIC (0.5 M), HOAt (0.5 M), 4.5% TPGS, 30 μl total volume, 45 °C, 3 h. Reactions proceeded to full conversion. Percentage of the by-product shown in parentheses.

	Amine	% Conversion	% Product		Amine	% Conversion	% Product
1		100	100	18		100	100
2		100	100	19		100	95
3		100	100	20		100	86
4		100	96	21		100	85
5		100	100	22		100	58
6		100	98	23		98	84
7		100	100	24		91	86
8		100	100	25		98	94
9		100	100	26		93	93
10		100	100	27		98	98
11		100	100	28		98	98
12		100	100	29		94	94
13		100	100	30		98	97
14		100	100	31		100	87
15		100	100	32		100	95
16		100	100	33		100	35
17		100	100	34		100	58