SEARCH Articles Figures Tables Addition reactions Diels-Alder reaction Diels hetero Diels-Alder addition Diels-Alder addition reaction Diels-Alder reactions additives Hetero addition Hetero-Diels-Alder Hetero-Diels-Alder reaction Hetero-Michael addition reaction Hetero-Michael additions Hetero-Michael reactions Michael hetero Reactions Michael addition