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

The reaction of N-isopropyl-2-(isopropylamino)troponimine [(i-Pr)(2)ATI]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 spectroscopic data suggest very symmetric structures for these molecules. The aluminum derivatives are monomeric in the solid state. Their crystal structures show planar, symmetric ring systems. The Al-N bond distances 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 synthesis of [(i-Pr)(2)ATI]H is also reported. The X-ray crystal data of [(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, beta = 109.14(2)degrees, V = 2874.4(14) Angstrom(3), monoclinic, space group 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 = 1615.6(3) Angstrom(3), orthorhombic, space group Pbcn, Z = 4, R = 0.0383.