The reactivity of decamethylsamarocene with polycyclic hydrocarbons and organo-main group complexes.

摘要

The limits of organosamarium(II) chemistry were probed by examining the reactivity of ({dollar}etasp5{dollar}-C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm, 1, with polycyclic aromatic hydrocarbons and organo-main group complexes. Although lanthanide complexes are thought to be mostly ionic in character and interactions of unsaturated systems with lanthanide metals were not previously expected, complex 1 reacts in arenes with polycyclic aromatic hydrocarbons and related nitrogen heterocycles with reduction potentials more positive than {dollar}-{dollar}2.22 V. The reactions of 1 and polycyclic aromatic hydrocarbons yield predominately bimetallic products of formula (({dollar}etasp5{dollar}-C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm) {dollar}sb2{dollar}(PAH) (PAH = anthracene, pyrene, 2,3-benzanthracene, 9-methylanthracene, and acenapthylene). The anthracene reaction product, (({dollar}etasp5{dollar}-C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm) {dollar}sb2{dollar} ({dollar}mu{dollar}-{dollar}etasp3{dollar}:{dollar}etasp3{dollar}-(C{dollar}sb{lcub}14{rcub}{dollar}H{dollar}sb{lcub}10{rcub}{dollar})), is unique in that the two equivalent (C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm units are located on either side of the nearly planar C{dollar}sb{lcub}14{rcub}{dollar}H{dollar}sb{lcub}10{rcub}{dollar} moiety. The pyrene reaction product, (({dollar}etasp5{dollar}-C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm) {dollar}sb2{dollar} ({dollar}mu{dollar}-{dollar}etasp3{dollar}:{dollar}etasp3{dollar}-(C{dollar}sb{lcub}16{rcub}{dollar}H{dollar}sb{lcub}10{rcub}{dollar})), is similar in that both (C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm units are on opposite sides of the planar pyrene ring, but in this case they are located asymmetrically at the same end of the pyrene. The reaction of 1 and phenazine produces a bimetallic product analogous to the anthracene complex, (({dollar}etasp5{dollar}-C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm) {dollar}sb2{dollar} ({dollar}mu{dollar}-{dollar}etasp3{dollar}:{dollar}etasp3{dollar}-(C{dollar}sb{lcub}12{rcub}{dollar}H{dollar}sb8{dollar}N{dollar}sb2{dollar})), but a reductively coupled product is observed in the reaction of 1 with acridine, (({dollar}etasp5{dollar}-C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm) {dollar}sb2{dollar}- ({dollar} mu{dollar}-{dollar}etasp3{dollar}:{dollar}etasp3{dollar}-(C{dollar}sb{lcub}13{rcub}{dollar}H{dollar}sb9{dollar}N){dollar}sb2{dollar}). Complex 1 reacts with cyclooctatetraene to form the tris(pentamethylcyclopentadienyl) complex, ({dollar}etasp5{dollar}-C{dollar}sb5{dollar}Me{dollar}sb5)sb3{dollar}Sm, a complex not expected to exist due to the extreme steric demands of the large C{dollar}sb5{dollar}Me{dollar}sb5{dollar} ligands. The reactions of 1 with azulene and decacyclene also produce (C{dollar}sb5{dollar}Me{dollar}sb5)sb3{dollar}Sm. 1 reacts with BiPh{dollar}sb3{dollar} by completely cleaving all the Bi-Ph bonds to form ((C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm) {dollar}sb2(mu{dollar}-{dollar}etasp2{dollar}:{dollar}eta sp2{dollar}-Bi{dollar}sb2{dollar}), which is the first example of a complex containing a planar M{dollar}sb2(mu{dollar}-{dollar}etasp2{dollar}:{dollar}etasp2{dollar}-Bi{dollar}sb2{dollar}) unit. The analogous reaction of 1 with SbBu{dollar}sp{lcub}rm n{rcub}sb3{dollar} led to isolation of ((C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm) {dollar}sb3{dollar}({dollar}mu{dollar}-{dollar}etasp2{dollar}:{dollar} etasp2{dollar}:{dollar}etasp1{dollar}-Sb{dollar}sb3{dollar})(THF) which contains the Zintl ion Sb{dollar}sb3sp{lcub}3-{rcub}{dollar}. This ion was postulated to exist as early as 1931, but had never been structurally characterized. The coordination chemistry of the organosamarium oxide complex, ((C{dollar}sb5{dollar}Me{dollar}sb5)sb2{dollar}Sm) {dollar}sb2(mu{dollar}-O), was investigated