ALUMINUM DERIVATIVES OF N-ISOPROPYL-2-(ISOPROPYLAMINO)TROPONIMINE

The reaction of N-isopropyl-2-(isopropylamino)troponimine [(i-Pr)(2)AT I]H, with Me(3)N . AlH3 or AlMe(3) gave [(i-Pr)(2)ATI]AlH2 or [(i-Pr)( 2)ATI]AlMe(2) in quantitative yield. The solution H-1 and C-13 NMR spe ctroscopic data suggest very symmetric structures for these molecules. The aluminum derivatives are monomeric in the solid state. Their crys tal structures show planar, symmetric ring systems. The Al-N bond dist ances for [(i-Pr)(2)ATI]- AlH2 and [(i-Pr)(2)ATI]AlMe(2) are 1.882(3), 1.886(4), and 1.915(1) A, respectively. A high yield method for the s ynthesis of [(i-Pr)(2)ATI]H is also reported. The X-ray crystal data o f [(i-Pr)(2)ATI]H revealed a planar ring but with two different C-ring -N distances. Crystal data with Mo K alpha (lambda = 0.710 73 Angstrom ) at 193 K: [(i-Pr)(2)ATI]H, C13H20N2, a = b = 15.469(1) Angstrom, c = 9.099(2) Angstrom, V = 1885.9(4) Angstrom(3), trigonal, space group < P(3)over bar>, Z = 6, R = 0.0464; [(i-Pr)(2)ATI]AlH2, C13H21AlN2, a = 16.681(4) Angstrom, b = 9.739(2) Angstrom, c = 18.730(5) Angstrom, bet a = 109.14(2)degrees, V = 2874.4(14) Angstrom(3), monoclinic, space gr oup P2(1)/c, Z = 8, R = 0.0536; [(i-Pr)(2)ATI]AlMe(2), C15H25AlN2, a 9 .824(1) Angstrom, b = 17.022(1) Angstrom, c = 9.661(1) Angstrom, V = 1 615.6(3) Angstrom(3), orthorhombic, space group Pbcn, Z = 4, R = 0.038 3.