The Roskamp reaction was first discovered by and co-workers in 1989. This reaction is very useful in synthesizing from aldehydes and , using various Lewis acids as catalysts (such as BF3, SnCl2, GeCl2). The two most noteworthy aspects of the Roskamp reaction are mild conditions and selectivity. Usually it only takes no more than one hour at room temperature to completely convert the starting materials to products.