Next the scope of the aldehyde component was investigated. Electron donating (OMe), neutral (Me) and withdrawing (CF3) substituents were probed at ortho-, meta-and para-positions in a 3´3 array (Scheme 2b), revealing electron-rich substrates tended to be most reactive. Symmetrical 4-methoxybenzaldehyde gave an 87% combined yield of mono and di-functionalization (1:1.1 mono:di). Substrates with the methoxy group in the ortho-and meta-positions gave slightly reduced yields. This contrasts with the Me and CF3 substituted systems, where increased yield was observed with ortho-substitution. Electron poor derivatives gave lower overall yields and reduced di-functionalization.