1-Piperidino-1-cyclohexanecarbonitrile is a precursor to the manufacture of Phencyclidine (PCP) which is an anesthetic and controlled substance. 1-Piperidino-1-cyclohexanecarbonitrile is found have a toxicity that is three times greater than that of Phencyclidine.

1-Piperidinocyclohexanecarbonitrile:
https://cymitquimica.com/products/TR-P480040/3867-15-0/1-piperidinocyclohexanecarbonitrile/

Definition:
1-piperidinocyclohexanecarbonitrile intermediate in the chemical synthesis of phencyclidine; imperfectly synthesized PCP correlated with undue toxic effects; structure:

http://www.reference.md/files/C011/mC011993.html

The original chemistry laying the groundwork for the preparation of phencyclidine (PCP) was a study reported in 1926 describing the reaction of 1-piperidinocyclohexanecarbonitrile (PCC) with Grignard reagents. It was not until some 30 years later that the anesthetic effectiveness was observed in animals, and the compound was made available

Illicit Synthesis of Phencyclidine (PCP) and Several of Its Analogs (1976):
https://www.designer-drug.com/pte/12.162.180.114/dcd/chemistry/pcp.shulgin.html

• There have been some posts in other places suggesting that there is a bad synth of 3-MeO-PCP with a large percent of 1-piperidinocyclohexanecarbonitrile (PCC) contaminant. This is less than ideal but what are the real risks? Obviously, people are worried about that carbonitrile group dissociating to form HCN, but wouldn't an acidic hydrolysis of the nitrile group with HCL (Which happens to be present in the 3-MeO-PCP salt and in stomach acid for that matter) replace the nitrogen atom with hydrogen effectively rendering the PCC harmless in a solution before ingestion? Or is my whole premise off?

Is PCC really a problem?:
https://www.reddit.com/r/AskDrugNerds/comments/81tcag/is_pcc_really_a_problem/

Abstract:
A retrospective study of illicit phencyclidine (PCP), which consisted of 94 different cases or 213 individual samples, has shown that one third of both the powder/tablets and green plant material contained the synthetic contaminant 1-piperidinocyclohexanecarbonitrile (PCC). The mole % PCC/PCP ranged from 1 to 68%.

(1980) Contamination of illicit phencyclidine with 1-piperidinocyclohexanecarbonitrile:
https://pubmed.ncbi.nlm.nih.gov/7442133/

1-Piperidine Cyclohexane Carbonitrile Safety Data Sheet (PDF 5 pages):
https://www.caymanchem.com/msdss/20367m.pdf

1-piperidinocyclohexanecarbonitrile:
https://www.wikidata.org/wiki/Q27092788