Often I find that companies request a particular pantone color they would like to use for their logo along with the cmyk equivalent.
Is it not imperative to give the pantone designator that comes after the number? i.e. 286 "C" or "CP"
I'm usually only given the number portion. Let's use these as an example
Pantone 286 or C100 M66 Y0 K2
Go ahead make those two separate shapes using Pantone 286C and the CMYK values. The colors are nowhere near each other. 286 CP, however, is much closer to the CMYK value.
There're several issues regarding this. Usually, the most common Pantone libraries are the "Pantone solid Coated" for coated papers (ie 286C) or Uncorated paper (such as 286U) The main problem is to find the equivalent color, since not all Pantone can be printed as CMYK (really, only a few Pantone colors have an accurate CMYK or RGB equivalent). The most exact equvalent is the use of the Pantone Color Bridge (but only using the printed library, you can't use what you see on the monitor as reference. Since Pantone are L*a*b color, you can't even use RGB as reference, so what you see on the monitor could be very different than the printed result. Some Pantone are almost impossible to convert to RGB or CMYK