Tetrabutylmanganese ate complex 'Bu4MnLi2' reacts with allylic and prop-2-ynylic bromides to generate the corresponding allyl-and prop-2-ynyl-manganese species which further react with electrophiles such as aldehydes, ketones, epoxide and chlorosilanes to afford the corresponding allylated and prop-2-ynylated and/or allenylated products in high yields.