Synthesis and reactivity of bimetallic bridging haloalkyl complexes of the formula [(.eta.5-C5H5)Re(NO)(PPh3)X(CH2)xM(CO)5]+ BF4- (X = iodo, bromo, chloro; M = rhenium, manganese; x = 1, 4) Academic Article uri icon

abstract

  • Reactions of (CO) 5 ReCH 2 OCH 3 with (CH 3 ) 3 SiI, (CH 3 ) 3 SiBr, and HCl gas give the halomethyl complexes (CO) 5 ReCH 2 X (4, 76–92%; X = a, I; b, Br; c, Cl). Reactions of Na + [(CO) 5 Re] − with ICH 2 F and I(CH 2 ) 4 I give (CO) 5 ReCH 2 F (4d, 73%) and (CO) 5 Re(CH 2 ) 4 I (5, 36%). Reactions of the substitution-labile dichloromethane complex [(η 5 -C 5 H 5 )Re(NO)(PPh 3 )(ClCH 2 Cl)] + BF 4− (2) with 4a and 5 give bridging haloalkyl complexes [(η 5 -C 5 H 5 )Re(NO) (PPh 3 )I(CH 2 ) x Re(CO) 5 ] + BF 4− (x = 1, 6a; x = 4, 7) in 69–78% yields after workup. A similar reaction of 2 and (CO) 5 MnCH 2 I gives [(η 5 -C 5 H 5 )Re(NO)(PPh 3 )ICH 2 Mn(CO) 5 ] + BF 4− (9), which is less stable than 6a but can be isolated in crude form. The XCH 213 C NMR resonances of 6a, 7, and 9 show diagnostic downfield shifts, and the diastereotopic XCH 2 protons give distinct 1 H NMR resonances. Reactions of 2 with 4b,c (−80 to −25 °C) give spectroscopically observable adducts [(η 5 -C 5 H 5 )Re(NO)-(PPh 3 )XCH 2 Re(CO) 5 ] + BF 4− (X = Br, Cl). Reaction of 2 and 4d does not yield a detectable bridging fluoroalkyl complex. Addition of PPN + Br − to 6a gives (η 5 -C 5 H 5 )Re(NO)(PPh 3 )(I) (78%) and 4b (82%), and similar reactions of 9 are described. © 1993, American Chemical Society. All rights reserved.

author list (cited authors)

  • Zhou, Y., & Gladysz, J. A.

citation count

  • 7

publication date

  • April 1993