It is recently reported that the radical reaction is used for the organic synthesis as a useful method of bond formation.
We have developed various azoic radical initiators, and we apply the process development for the organic synthesis with those unique initiators. We perform the effective and stereoselective reactions by selecting the radical initiators suitable for the reaction condition and/or reaction system of the compound requested from customers.

V-70

Example 1

Initiator	Time(hr)	Yield(%)of 3a
AIBN	24	No Reaction
BPO	24	No Reaction
Et3B	18	44
hv	6	85
V-70	12	89

By using V-70, which is a polymerization initiator at low temperature, as a radical initiator, the reaction with bromo malononitrile which tends to decompose or disproportionate with heat proceeds effectively under room temperature.

Example 2

Initiator	Solvent	Temp. (℃)	Yield (%)	Ratio (anti:syn)
hv	CH2Cl2	refl.	86	94:6
Et3B	CH2Cl2	-78	69	99:1
AIBN	C6H6	refl.	80	86:14
V-70L	CH2Cl2	r.t.	85	98:2

The above table shows the effect by each radical initiator with Z-bromopentanoic acid ester in the intramolecular cyclization reaction. Compared with the results with Et3B and AIBN, the result with V-70L shows higher yield and higher stereoselectivity of product materials.

Reference

Y. Kita, A. Sano, T. Yamaguchi, M. Oka, K. Gotanda, M. Matsugi,Tetrahedron Lett., 38, 3549 (1997)
M. Matsugi, K. Gotanda, C. Ohira, M. Suemura, A. Sano, Y. Kita,J. Org. Chem., 64, 6928　(1999)