4-Oxo-tempo , Tempone

This compound appears as a bright orange crystalline solid with a melting range of 33–38°C.The estimated boiling point is 299.88°C,and the approximate density is 1.0710.The vapor pressure at 25°C is 2.254 Pa,and the refractive index is around 1.4640.Storage at 2–8°C is advised.It is soluble in DMF,DMSO,ethanol,and PBS(pH 7.2)at concentrations up to 30 mg/ml and is partly soluble in water,acetone,and diethyl ether.The stable nitroxide radical requires storage in a sealed,moisture-proof,light-proof container away from strong oxidants,reducers,and excessive heat(>100°C).The ketone group at the 4-position enhances its overall structural stability.

4-Oxo-TEMPO(CAS No.2896-70-0)is a ketone-functionalized derivative of the TEMPO radical,featuring a carbonyl group at the 4-position of the piperidine ring.This modification slightly alters its polarity and redox potential compared to TEMPO,making it particularly useful in aqueous-phase catalysis and as a spin probe in polar environments.

1.Water-Compatible Oxidation Catalyst
Enables the selective oxidation of water-soluble carbohydrates(e.g.,glucose to glucaric acid)in biphasic systems.Its higher polarity improves catalyst recovery and recyclability in continuous flow reactors for green chemistry applications.

2.Dynamic Nuclear Polarization(DNP)Agent
Used to enhance NMR sensitivity in solid-state magic-angle spinning(MAS)NMR.It acts as a polarizing agent for analyzing pharmaceutical polymorphs and membrane protein structures at atomic resolution.

3.Functionalization of Nanomaterials
Serves as a grafting agent for carbon nanotubes and graphene oxide.The radical facilitates covalent attachment to sp²carbon surfaces,improving dispersion in polymer matrices for high-strength nanocomposites.

4.Radical Scavenger in Photoresists
Incorporated into extreme ultraviolet(EUV)photoresist formulations to control acid diffusion and mitigate stochastic defects,enabling higher resolution patterning for next-generation semiconductor manufacturing.