Phenacaine

Phenacaine

Names
IUPAC name (1E)-N,N′-Bis(4-ethoxyphenyl)ethanimidamide
Identifiers
CAS Number	101-93-9
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL127123
ChemSpider	7307
PubChem CID	7588
UNII	V3M4D317W8 Y
InChI InChI=1S/C18H22N2O2/c1-4-21-17-10-6-15(7-11-17)19-14(3)20-16-8-12-18(13-9-16)22-5-2/h6-13H,4-5H2,1-3H3,(H,19,20)
SMILES O(c1ccc(cc1)N\C(=N\c2ccc(OCC)cc2)C)CC
Properties
Chemical formula	C18H22N2O2
Molar mass	298.386 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Phenacaine, also known as holocaine, is a local anesthetic. It is approved for ophthalmic use.

Synthesis

Synthesis:

The condensation of P-Phenetidine (1) with triethyl orthoacetate [78-39-7] (2) to afford the imino ether (a so-called Pinner salt) (3). Reaction of that intermediate with a second equivalent of the aniline results (4) in a net displacement of ethanol, probably by an addition-elimination scheme. There is thus obtained the amidine, phenacaine (5).

In the patented synthesis, phenacetin was used as precursor. Treatment with PCl3 gave the enol chloride, and reaction of this intermediate with p-phenetidine then completed the synthesis of phenacaine.