Seems like an interesting method to me :
http://www.f.u-tokyo.ac.jp/~fukuyama/slide/2001-yugokyokanto-hayashi.pdf (http://www.f.u-tokyo.ac.jp/~fukuyama/slide/2001-yugokyokanto-hayashi.pdf)
What I like, is that one can use mercaptanes istead of some Sn-compounds to get all sorts of different 3-idoles. - 2 last pages of the pdf
Overall, seems rather impractical for tryptamine derivates,
but, in my opionion, most definetly worth keeping in mind.
One would need Me2N-CH2-CH2-CHO, I guess.
Z_H