REAKTIONSVERHALTEN METALLKOORDINIERTER 1-MOLYBDA-2-PHOSPHA-1,3-DIENE GEGENUBER ALKINEN UND DIINEN

Abstract Treatment of η 2 -{(R 1 )[(Ph)(H)CCH]P[Mo]}Fe(CO) 4 ( 1 ) or η 4 -{(R 1 )[(Ph)(H)CCH]P[Mo]}Fe(CO) 3 ( 2 ) {[Mo] = Mo(η 5 -C 5 H 5 )(CO) 2 ; R 1 = 2,4,6- t Bu 3 C 6 H 2 O} with HCCR 2 [ 3a : R 2 = (CH 2 ) 2 CH 3 ; 3b : R 2 = Ph] or HCCC 6 H 4 CCH ( 5 ) produces complexes [ 4a : R 2 = (CH 2 ) 2 CH 3 ; 4b : R 2 = Ph] or {ν 3 -{(R 1 )− ( 6 ) respectively. Each of these molecules contains a 1-ferraallyl moiety, which is η 3 -coordinated to an [Mo] building block. A possible reaction sequence for the formation of compounds 4 and 6 is described. The presented mechanism is corroborated by systematic studies of the reaction behaviour of 2 with different Lewis bases L [L = CO, PPh 3 , PPh 2 (CCPh)]. As an initial step, the formation of η 2 -{(R 1 )[(Ph)(H)CCH]P[Mo]}Fe(CO) 3 (L) [ 1 : L = CO; 8a : L = PPh 3 ; 8b : L = PPh 2 (CCPh)] is discussed. The result of the X-ray structure analysis of compound ν 3 -{(R 1 )[(Ph)(H)C= CH]- ( 4b ) is reported. 4b crystallizes in the triclinic space group P 1 with the cell parameters a = 1064.7(2), b = 1411.0(3), c = 1617.3(4)pm, α = 81.74(2), β = 80.89(2), γ = 73.05(2)°, V = 2282.5(9) × 10 6 pm 3 and Z = 2.