Table 3.

Effects of Order of Addition on the Multi-Component Aziridination.^a

procedure		reaction protocol	% yield 5a b	% ee 5a c
IVd	A + B + C + E		94	98
Ve	A + B + D* + E + C * plus 4 Å MS		85 f	98
VIg	A + B + D* + E * plus 4 Å MS		<1	–
VIIh	A + B + D* + E *plus 4 Å MS		–	–

^aAll reactions were performed as described in Table 2.

^bIsolated yield after chromatography on silica gel. Analysis of the crude reaction mixture indicates =50:1 cis:trans selectivity for 5a.

^cDetermined on purified cis-5a by HPLC.

^dThe diazo compound E is added to a mixture of A, B and C and then toluene is added and the mixture stirred at 25 °C for 1 h after which 4 Å powdered molecular sieves and D are added and the mixture stirred for 24 h at 25 °C.

^eA mixture of A, B, 4 Å MS, D, E and C, added in that order, was dissolved in toluene and the resulting solution allowed to stir for 24 h at 25 °C.

^fA 3% yield of enamines 18a and 19a was observed.

^gA mixture of A, B, 4 Å MS, D and E, added in that order, was dissolved in toluene and the resulting solution allowed to stir for 2 min at 25 °C before C was added and the resulting solution stirred for 24 h at 25 °C. The products of this reaction are shown in Figure 6.

^hSame as procedure VI except that C was not added. The products from this reaction are 13a (5%), 14a (<1%), 15a (5%), 16a (11%), 17a (38%) and 12 (37%).