Primarily as an initiator in radical reactions. Prepn: A. Stock, F. Zeidler, Ber. 78, 531 (1921); E. C. Ashby, J. Am. Chem. Soc. 81, 4791 (1959). Use as protecting group: C. Lutz et al., Tetrahedron 54, 10317 (1998); as transfer reagent in polymerizations: V. Beraud et al., Macromol. Rapid Commun. 21, 901 (2000); as stereoselective intiator for hydrometalation: K. Takami et al., J. Org. Chem. 68, 6627 (2003). Review of radical reactivity in generation of carbon-centered radicals: C. Ollivier, P. Renaud, Chem. Rev. 101, 3415-3434 (2001). Brief review of application in radical initiation and in non-radical processes: G. O'Mahony, Synlett 2004, 572-573.