Abstract
The field dependence of CIDNP effects in gas-phase biradical reactions is for the first time detected during the photolysis of the homological series of cyclic aliphatic ketones from cyclodecanone to cyclopentadecanone. The influence of magnetic field on nuclear polarization is studied up to 0.47 T. The experimental data are interpreted on the basis of nuclear-spin-selective ST − transitions in intermediate biradicals. In contrast to liquid-phase reactions, mainly protons in the γ-position are polarized. The relatively weak α-CH 2 and β-CH 2 protons in the gas are explained by compensation of various conversion channels in biradicals. The strong spin—rotation interaction in gases excludes polarization transfer observed in solutions. The field dependence of CIDNP effects differs noticeably in gases and liquids. It is associated with the different dynamics of conformational motion in liquids and gases.
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.
