Reactions of amides with organoaluminium: a useful synthetic route to aluminium diketiminates

摘要

The raction of N-tert-butylbenzamide (~tBuNHCOPh) with 1.1 molar equivalents of Me_3Al in refluxing hexane afforded a five-coordinated dimeric compund [Me_2Al{#eta#~2-~tBuNC(Ph)(#mu#-O)}]_2 1, whereas 2.2 molar equivalents yielded a monomeric compound [Me_2Al{#eta#~2-~tBuNC(Ph)(#mu#-O)}AlMe_3]2. Reactionof PhCONHAr with l molar equivalent of Me_3Al in toluene at 25 deg C, gave four-coordinated imeric eight-membered ring compunds [Me_2Al{#mu#-#eta#~2-(p-XC_6H_4)NC(Ph)O}]_2 (X = OMe 3 or 4). Benzanilide (PhNHCOPh) with 1.2 molar equivalents of Me_3Al in refluxing toluene resulted inaluminium amidate 4 and a trace amount of an aluminium diketiminate. [Me_2Al{#eta#~2-PhNC(Ph)C(H)C(Ph)NPh}] 5. Furthermore. PhCONHC_6H_4X-p reacts with 2 molar equivalents of R_3Al in refluxing toluene affording aluiniumdiketiminate compounds. [R_2Al{#eta#~2-(p-XC_6H_4)NC(Ph)C(R')C(Ph)-N(pXC_6H_4)}] (R = Et, R' = Me, X = H 6: R = Et, R' = Me, X = Cl 7; R = Me, R' = H, X = Cl 8; R = Me, R' = H, X = Me 9; R = Et, R' = Me, X = Me 10). Thus, this proces offers a readily available synthetic route to the preparation of aluminium diketiminates which is otherwise difficult with aromatic substituents