An efficient procedure for the regiocontrolled synthesis of a-phenylseleno ketones has been developed, making use of the lithium naphthalenide induced reductive selenenylation of the alpha-cyano ketone system as a key operation. Moreover, seleno ketones thus generated in situ, upon subsequent treatment with hydrogen peroxide and acetic acid, could be further converted into the corresponding enones with a high degree of regioselectivity, presumably due to the lithium salt mediated selenoxide syn-elimination process.
