PPh3-mediated intramolecular conjugation of alkyl halides with electron-deficient olefins: facile synthesis of chromans and relevant analogues

With the mediation of phosphine, the direct intramolecular coupling of two electrophiles - alkyl halides with electron-deficient olefins has been successfully realized in an intramolecular conjugate addition manner. The reaction provides a new approach for the synthesis of chromans and relevant analogues.