Spirodecanone


Spirodecanone refers to a class of spirocyclic ketones, often studied for their potential applications in medicinal chemistry. One notable example is 1-Phenyl-1,3,8-triazaspirodecan-4-one, which has been investigated as a metabolite of neuroleptic agents like Fluspirilene. It has a molecular formula of and a melting point of 188-191 °C.

Synthesis

The original synthesis was first disclosed by Paul Janssen, and was covered by Daniel Lednicer in one of his books.
A recent synthesis of spirodecanone is disclosed:
The Strecker-like condensation between N-benzyl-4-piperidone , aniline and TMSCN , gives 4-anilino-1-benzylpiperidine-4-carbonitrile . Acid catalyzed partial hydrolysis of the nitrile to the amide afforded 4-anilino-1-benzylpiperidine-4-carboxamide . Reaction with forms the spiroimidazolidone ring giving 8-benzyl-1-phenyl-1,3,8-triazaspirodec-2-en-4-one . The imine bond is reduced with sodium borohydride giving 8-benzyl-1-phenyl-1,3,8-triaza-spirodecan-4-one . Catalytic hydrogenation then removes the benzyl group.
It is noteworthy to mention that intermediate 4 finds dual use in the synthesis of some highly potent fentanyl analogs.

Applications

Listed in alphabetical order:
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  1. is similar but with additional para-fluoro.
  2. Fluspirilene
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  1. R-5260
  2. R 6890
  4. Spiramide
  5. Spiroxatrine contains a Benzodioxan sidechain.
  7. Spiperone
  8. Ro64-6198 & Ro65-6570.
  9. BRN 4620880
  10. .