Table 1.

1, 3-Dipolar cycloadditions of TMS diazomethane and various dipolarophiles

Entry	Cmpd.	R	R’	Cycloaddition Conditions	%Yielda	Product Ratio a:b:c	Relative configuration of 1-pyrazoline (3, 5 trans: 3, 5-cis)
1	5	H	Me	2 eq. TMSCHN2, PhCH3 / hexane (1:1), rt, 8.5 hr	20b	0:60:40	Not determined
2	6	H	Et	1.5 eq. TMSCHN2, C6H6/ hexane (1:1), rt, 24 hr	90	0:35:65	50:50
3	7	H	t-Bu	1.2 eq. TMSCHN2, C6H6/ hexane (1:1), rt, 24 hr	71	0:44:56	50:50
4	8	H	Mtc	1.5 eq. TMSCHN2, C6H6/ hexane (1:1), rt, 24 hr	50	0:45:55	50:50
5	9	Me	Et	3 eq. TMSCHN2, C6H6/ hexane (1:1), reflux, 8.5 hr	40	0:37:63	6:94
6	9	Me	Et	3 eq. TMSCHN2, Toluene, reflux, 8.5 hr	49	16:16:68	50:50
7	10	Me	t-Bu	2 eq. TMSCHN2, C6H6/ hexane (1:1), reflux, 8 hr	47	0:76:24	Not determined
8	11	Me	Mt	2 eq. TMSCHN2, C6H6/ hexane (1:1), reflux, 8 hr	62	0:5050	Not determined
9	12	Ph	Et	2 eq. TMSCHN2, C6H6/ hexane (1:1), rt, 8 hr	7.5	5:20:75	7:93
10	12	Ph	Et	2 eq. TMSCHN2, C6H6/ hexane reflux, 8 hr	-	Complex mixture	Not determined
11	13	Ph	t-Bu	2 eq. TMSCHN2, C6H6/ hexane (1:1), reflux, 8 hr	35	11:33:56	10:90
12	13	Ph	t-Bu	2 eq. TMSCHN2, Toluene, reflux, 8.5 hr (1:1), reflux, 8 hr	45	43:43:14	50:50
13	14	Ph	Mt	2 eq. TMSCHN2, C6H6/ hexane (1:1), reflux, 8 hr	71	24:0:76	100:0 (2-pyrazoline)

^aIsolated yield.

^bYield based on acryloyl chloride.

^cMt = menthyl.