Abstract
The reaction of diimine Ia with chlorophosphite II proceeds readily in the methylene chloride medium to afford salt IVa as a mixture of two diastereomers, as follows from the P NMR spectrum of the reaction mixture, which contains two singlet peaks at –114.41 and –115.04 ppm in a 1:1 ratio. Compound IVa contains three chiral centers but is formed only as a mixture of two diastereomers, indicating that the process of cascade cyclization occurs with a high stereoselectivity. Salt IVa loses hydrogen chloride molecule under treating with triethylamine turning into neutral product Va (δР –102.42, –102.85 ppm). In view of the data, we introduced optically pure diimine Ib into the reaction with 2-chloro-4,5-dimethyl-1,3,2-dioxaphospholane III to isolate phosphorus-containing framework structures in optically pure form.
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.
