Abstract
With the objective of establishing why reaction of the proposed molecular motors 7 and 22 with carbonyldiimidazole and phosgene does not result in unidirectional rotation, N-ethyl-2-[4-( N, N-dimethylamino)-2-pyridinyl]benzenamine [ 28, 2-(2-(ethylamino)phenyl)DMAP] was examined as a model substrate. The synthesis of 28 is described. Compound 28 was found to react with phosgene to give the unexpectedly stable N-acyl pyridinium salt 30. The latter ( 30) is so stable that it is effectively inert to reaction with methanol. At room temperature the two methyls in the Me 2N-group of 30 are nonequivalent (NMR) and the barrier to rotation around the Me 2N–pyridinium bond is 18.5 kcal/mol. To the authors' knowledge, that is the first quantitative determination of the barrier to rotation around the bond between a 4-( N, N-dimethylamino) group and an N-acyl pyridinium unit. The implications of the findings regarding 30 as to troubleshooting the proposed molecular motor 7, and possible strategies to follow, are discussed.
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.
