Thus, Giese demonstrated in the red

Thus, Giese demonstrated

in the reduction of 230 that high selectivites for the Felkin product 231 can be obtained by using sterically

demanding trapping reagents

which
deliver

a hydrogen atom

to the initially

formed radical 233. Stereoelectronic factors
seem to be an important factor in the control of the conformation of 233. The phenyl substituent assumes, as already discussed for the hydride reactions, the role of the substituent L even in the case of bulky substituents such as tert-butyl (Schemes 69 and 70, Table 33).
82 Likewise, alkoxy groups are able to stabilize the transition states in such radical reactions in the same way as that discussed for ionic reactions (Scheme 71, Table 34).
83 Interestingly, the radical addition of 2-iodopropane
to 237 (Table 35, entry 2) also yielded the Felkin