Potassium Carbonate → 2-(Phenylselanyl)aniline

Beteiligte Stoffe

Reaktionsschritte

Using this protocol (see example 4 below), phenyl selenol was coupled with electron-rich aryl iodides in very good yields (Table 5). Sterically hindered iodides such as those with ortho-functionalities (entries 3, 5, 7 and 11), were coupled, as well as aryl iodides containing heteroatoms (entry 8 and 10). When o-iodoaniline was used as the aryl halide, in addition to the desired selenide, products were observed arising from the self-coupling of o-iodoaniline. This problem also persisted with K3PO4. However, when K2CO3 was used as the base, 1-amino-2-phenylselanyl-benzene was isolated in 60% yield (entry 12). With electron-poor aryl iodides, in addition to the desired diaryl selenides, diaryl diselenides were observed if NaOt-Bu or K3PO4 was used. In addition, with NaOt-Bu, transesterifcation products were observed when aryl halides with ester groups were used. Such complications can be avoided if K2CO3 is used instead of NaOt-Bu or K3PO4. Using this modified protocol a variety of diaryl selenides were obtained from electron-poor aryl halides (Table 6). The protocol tolerates even base sensitive groups such as esters and ketones (entries 3, 4, and 6).

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