2- Pyrrolines synthesis

IH of allenic amines also occurs in the presence of silver salts. IH of a-allenic amines proceeds in good yields in the presence of AgBp4 and provides a useful method for 3-pyrrolines synthesis via Endo-Trig processes (Eq. 4.93) [314]. 

Curiously, the synthesis of shihunine via a phenylcyclopropylimine (187) is the sole example of a simple pyrrolidine alkaloid obtained according to this general pyrroline synthesis (188) (Scheme 40). 

Pyrrolines, formation by 1,3-dipolar cycloaddition 84BSB593. 2-Pyrrolines, synthesis via 1,5-dipolar cyclization 79CRV181. 

Scheme 8.17 [Cu(hfacac)2] catalyzed 3-pyrrolines synthesis via intermolecular [4-1-1] cycloaddition.

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