Abstract
Time-resolved chemically induced dynamic nuclear polarization (CIDNP) studies are reported for radical reactions following laser pulse excitation of 2,2,4,4-tetramethylpentan-3-one and 2,4-dihydroxy-2,4-dimethylpentan-3-one in various solvents and of acetone in propan-2-ol-d8. The results show that cross-relaxation does not lead to polarization of the protons of 2-hydroxy-2-propyl and tert-butyl radicals at the 4.7 T field of the CIDNP experiment. Effects previously ascribed to cross-relaxation for the acetone/propan-2-ol system are due to side reactions and a fast solvent dependent nuclear relaxation. In radicals containing hydroxy groups, the CIDNP is strongly influenced by hydrogen bonding, which also affects their OH to CH disproportionation ratios. Auxiliary CIDEP experiments with 2,4-dihydroxy-2,4-dimethylpentan-3-one clearly indicate that the triplet mechanism polarization for this ketone is in absorption.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
