KC Nicolaou and co-workers have reported in JACS on the synthesis of tubulysin and some analogs. There are some interesting propellane analogs that reminded me of the recent Baran paper in Science that involved some strain-release amination reactions – the Baran paper involved the use of strained rings that would react with free amines to form new C-N bonds. I like the analogy in this photograph, where the two co-first authors of the paper (holding hands) represent the “strained ring” and the “amine” is Phil Baran pouring a flask to break the strain.
One pot C-N bond formation (Science paper):
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