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Synthesis of Lewis acid/base-stabilized 13/15-compounds. Ulf Vogel AK Prof. Dr. M. Scheer. Motivation. Production of 13/15 thin layers by CVD processes etc. Problem: Control of stoichiometry is difficult especially for ternary phases like GaP x As 1-x.
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Synthesis of Lewis acid/base-stabilized 13/15-compounds Ulf Vogel AK Prof. Dr. M. Scheer
Motivation Production of 13/15 thin layers by CVD processes etc. Problem: Control of stoichiometry is difficult especially for ternary phases like GaPxAs1-x Solution: Single source precursors reflect the correct stoichiometry Problem:Organic substituents give rise to carbon contaminations during the CVD process High molecular weights often cause low vapor pressures Solution: Use of precursors with hydrogen substituents
13/15-Compounds with H-substituents tend to H2-eliminination und oligomerisation The coordination of Lewis acids and bases could stabilize these compounds 0 DH0 (kJ mol-1) - 88 - 129 - 239 Calculated stabilization energies
H2-Eliminiation • Salt metathesis P-E Bond formation in the coordination sphere of transition metals (E = B, Al, Ga) Synthesis of the starting compound
Synthesis of [(CO)5W(H2PEH2•NMe3)] (E = B, Al, Ga) H2-Elimination: Salt metathesis:
The structure of [(CO)5W(H2PEH2•NMe3)] (E = B, Al, Ga) E = B (Space group P21/c) W–P 254.2(2) P–B 195.5(5)B–N 160.3(5)B–P–W 116.4(1) N–B–P 116.0(3) E = Ga (Space group P21/c) W–P 253.7(2) P–Ga 234.9(2)Ga–N 203.9(7)Ga–P–W 114.72(7) N–Ga–P 107.4(2) W–P 254.91(9) P–Al 237.7(1) Al–N 203.6(3) Al···Al’ 290.8(2)Al–P–W 118.44(4) P–Al–N 103.28(8) Space group P21/c
Reaction of [(CO)5W(H2PAlH2•NMe3)] with Lewis Bases W1–P1 257.9(2) W2–P1 258.0(2) W1–P1–W2 126.79(7) Space group P21/n
Fast exchange between free and coordinated NMe3 W–P 256.6(1) Al–P 243.2(2)Al–N1 215.5(4) Al–N2 216.0(4)N1–Al–N2 171.1(2) Al–P–W 128.58(6) Space group P21/n
W1–P1 259.3(3) W2–P2 252.0(4)Al–P1 237.1(4) Al–P2 236.9(6)Al–P1‘ 237.5(5) Al–N 196(1)Al–P1–Al‘ 81.2(2) P1–Al–P1‘ 98.8(2)P2–Al–P1 111.1(2) P2–Al–P1‘ 112.6(2)W1–P1 259.3(3) W2–P2 252.0(4)Al–P1 237.1(4) Al–P2 236.9(6)Al–P1‘ 237.5(5) Al–N 196(1)Al–P1–Al‘ 81.2(2) P1–Al–P1‘ 98.8(2)P2–Al–P1 111.1(2) P2–Al–P1‘ 112.6(2) Space group P1
E = P E = As Pt–E 235.9(2) 247.21(9)Pt–P1 227.8(2) 228.4(2)Pt–P2 228.2(2) 228.4(2)W–E 260.3(3) 268.67(9)E–Pt–P1 98.01(8) 97.75(5)E–Pt–P2 97.87(8) 96.36(6)P1–Pt–P2 161.43(8) 162.40(6)Pt–E–W 132.4(1) 133.66(3)Sum of bond angles on Pt: 357.31(8) 356.51(6) Space group P21/n
31P{1H} NMR Spectrum ofcis/trans–[(CO)5W(m–PH2)Pt(H)(PPh3)2]
Pt–P1 233.0(2) Pt–P2 233.1(1)Pt–P3 231.0(2) P1–W 260.5(1)P1–B 198.1(6) Sum of bond angles on Pt: 359.87(5)° Space group: Pbcn Pt–P1 233.7(2) Pt–P2 228.5(2)Pt–P3 232.3(2) Pt–W 302.83(8)P1–W 246.0(2) P1–B 197.5(8)Sum of bond angles on Pt: 362.60(7)° Space group: P1
W–W‘ 304.1(1) W–P 250.1(3)W–P‘ 251.5(3) P–B 196(2)B–N 161(2)W–P–W‘ 74.63(9) P–W–W‘ 52.90(7)P–W'–W 52.47(7) P–W–P‘ 105.37(9)W–P–B 129.8(6) W'–P–B 114.0(5)P–B–N 117(1)W–W‘ 304.1(1) W–P 250.1(3)W–P‘ 251.5(3) P–B 196(2)B–N 161(2)W–P–W‘ 74.63(9) P–W–W‘ 52.90(7)P–W'–W 52.47(7) P–W–P‘ 105.37(9)W–P–B 129.8(6) W'–P–B 114.0(5)P–B–N 117(1) Space group: C2/c
W–P 257.4(6) W–I1 284.52(7) W–I2 286.60(9) P–B 196.7(8)B–N 159 (1)I1–W–I2 87.27(3) W–P–B 114.1(3)P–B–N 116.5(5) Space group: P21/c
Summary • The concept of P-E bond formation in the coordination sphere of transition metals was successfully used for the synthesis of transition metal complexes with 13/15 ligands • First synthesis of Lewis acid/base stabilized H2PEH2 (E = B, Al, Ga) • First synthesis of a transition metal complex with a cyclic Al2P2-ligand • Exploration of some reactions of [(CO)5W(H2PEH2•NMe3)] (E = B, Al)