WATER-SOLUBLE PHOSPHANES - 7 - SYNTHESIS, COORDINATION CHEMISTRY AND TEMPLATE REACTIONS OF PH-FUNCTIONAL BIS(PHOSPHINOETHYL)AMINES

Diprimary and disecondary bis(phosphinoethyl)amines RN[(CH2)(2)-PHR']( 2) (R = H, nBu, p-Tol; R'= H, Ph) (1a-1c, 2a) in addition to azaphosph orinanes (1d, 1e) are accessible by alkylation of PH3 or primary phosp hanes with bis(chloroethyl)amines in the superbasic medium DMSO/KOH. S equential P-methylation and N,P-silylation of 1a yields H-N[(CH2)(2)-P HMe](2) (2b) and the N- and P-trimethylsilyl derivatives Me3Si-N-[(CH2 )(2)-PHMe](2) (3a) and Me3Si-N[(CH2)(2)-P(SiMe3)Me](2) (3c). With C7H8 Mo(CO)(3) the potentially tridentate P2N hybrid ligands 1a, 1b (L) for m kinetically labile complexes fac-Mo(CO)(3)(L)(4a, 4b). Eight membere d chelate complexes cis-Mo(CO)(4)(L) (4c, 5a) are obtained on reaction of 1b and 2b (L) with C7H8Mo(CO)(4), the ligands L acting as P,P-bide ntates. The X-ray structure of 4c (space group Pbca) reveals a distort ed eight membered chelate ring system. By periphery reactions (P-metal lation, N-protonation and complexation with borane) a series of deriva tives (4d, 5b-5d) of 4c and 5a are accessible. A complex of a bidentat e ligand with terminal azaphosphorinane units (6b) is obtained by alky lation of 4d with nBuN[(CH2)(2)Cl](2). Attempts to form a twelve membe red tetradentate macrocycle by template mediated PH/C=C addition of di vinylphenylphosphine to 4a, 4b failed, however. The X-ray structure of the template 7a (space group P2(1)/c) formed initially from 4a shows the PhP(CH=CH2)(2) ligand to be in cis-position to the diprimary phosp hine which is coordinated to molybdenum via its P-atoms forming a fold ed eight membered ring system.