LAUSR

A MWI-promoted α-alkylation of ketones by using cycloalkanes as the alkylating agents under metal-free conditions is presented. Mechanistically, this alkylation involves a TBP-initiated and MWI-assisted formation of the required cycloalkyl radical and the α-ketone carbon radical followed by their selective cross coupling. To our knowledge, this should be the first example in which simple ketones and 1,3-diketones were efficiently alkylated with cycloalkanes via a cross-dehydrogenative coupling of C(sp3)−H bonds in the absence of any metal catalyst. Compared with literature methods, this new alkylation protocol has advantages such as cheap and abundant substrates, free of metal catalyst, good atom-economy and sustainability. As a further aspect, the substituted ketone obtained herein was found to be valuable intermediate for the preparation of the synthetically and biologically valuable tri-substituted alkene.