Nitrile oxide type cycloadditions seem to be the rage right now, as evidenced by TotSyn's account of Ley's bengazole synthesis. Here's a concise Philip Fuchs synthesis of the histrionical histrionicotoxin, one of those notorious frog alkaloids each of which seems to take the brain to some kind of high.
I liked the way the delicate N-O bond is formed at an early stage, and kept intact till the end, when it is cleaved by Zn-AcOH. The formation of two aldehydes leading to the two enynes, was slotted to happen to from the start as can be seen.
JACS (Communication) DOI: 10.1021/ja065015x
1 day ago in Variety of Life