Abstract
Wittig homologation of 2-(chloromethyl)-2H-chromen-2-ol derivatives 2a–t with (ethoxycarbonylmethylene)triphenylphosphorane provided the 2-oxoethylidene-2,3-dihydrobenzoxepine-4-carboxy-lates 3a–t with Z (cis) selectivity. Various basic catalysts were studied for the reaction of 2-(chloromethyl)-2H-chromen-2-ol 2a with the combination of Wittig reagent to provide compound 3b. The reaction of 2-(chloromethyl)-2H-chromen-2-ol 2a with other Wittig reagents, such as methylene(triphenylene)phosphorane and (1-ethoxycarbonylethylidene)triphenylphosphorane provided ketone derivative 4a rather 2-oxoethylidene derivative 3b. The ketone derivative 4a was reacted with Wittig reagent (ethoxycarbonylmethylene)triphenylphosphorane to give 2,3-dihydrobenzoxepine-4-carboxylate 3b. The present approach is novel, straight forward and being reported for the first time.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.