[PRAGATI1]

What can be added to cyclohexane amine or alchohol as a chromophoric group?

[pgk]

Amidation or esterification with 4-methoxycinnamic acid, respectively that lead to a strong UV absorption at ≈ 300 nm.

[PRAGATI1]

do i need to give heat? i want to add chromophore group at RT or by vortexing?

[pgk]

1). Yes, you need to heat.
2). If you do not want to heat, just dissolve your amine or your alcohol with benzoic anhydride in dichloromethane, at 1/1.1 molar ratio and “vortex” it for 2 h at room temperature and then add aqueous NaOH or aqueous KOH at 1.5 molar ratio and shake it for a few minutes. The organic phase (the bottom layer) contains the benzoate derivative, which absorbs at ≈ 270-280 nm.
Hint: wear safety glasses, while working and take care of possibly exothermic reactions.   

[wildfyr]

For the cyclohexylamine, a huge variety of dyes come as NHS esters. They will react almost immediately and quantitatively with amines at room temperature, and can be separated by simple liquid/liquid extraction or a quick column. I would choose a dye that has poor water solubility to make for easier purification.

[PRAGATI1]

thank you that would work as i need to simply attach a molecule for identification under UV.