Deprotonation of rhenium terminal acetylide complexes (.eta.5-C5R5)Re(NO)(PPh3)(C.tplbond.CH): generation and reactivity of rhenium/lithium C2 complexes Academic Article uri icon

abstract

  • Reactions of methyl complexes (η5-C5R4R′)Re(NO)(PPh3)(CH3) (R/R′ ≡ H/H, H/CH3, CH3/CH3) with HBF4·OEt2, chlorobenzene, and R″C≡CH (R″ ≡ H, CH3) give terminal alkyne complexes [(η5-C5R4R′)-Re(NO)(PPh3)(R″C≡CH)]+BF4− (72–87%). When R″ ≡ CH3, equilibria with methylvinylidene complexes [(η5-C5R4R′)Re(NO)(PPh3)(≡C≡CHCH3)]+BF4− can be effected at 90–65 °C (75–99% conversion). Treatment of the alkyne or vinylidene complexes with t-BuO−K+ gives acetylide complexes (η5-C5R4R′)-Re(NO)(PPh3)(C≡CR″) (R/R′/R″: 1, H/H/H; 3, H/H/CH3; 11, H/CH3/H; 12, H/CH3/CH3; 2, CH3/CH3/H; 17, CH3/CH3/CH3; 81–94%). Reactions of 1 with 1.0 and 2.0 equiv of n-BuLi give the lithiated complexes (η5-C5H5)Re(NO) (PPh3) (C≡CLi) and (η5-C5H4Li)Re(NO) (PPh3) (C≡CLi), respectively, as assayed by 31P NMR and subsequent conversion with CH3I to 3 and 12. Reaction of 1 with 2.0 equiv of n-BuLi and Ph3SnCl gives the stannylated complex (η5-C5H4SnPh3)Re(NO)(PPh3)(C≡CSnPh3) (49%), which upon silica gel chromatography yields (η5-C5H4SnPh3)Re(NO)(PPh3)(C≡CH). Reaction of 2 with n-BuLi gives (η5-C5(CH3)5)Re(NO)(PPh3)(C≡CLi), as assayed by subsequent reactions with CH3I, D2O, Me3SiCl, and Ph3SnCl to give 17 (95%), 2-d1 (88%; 86-89% labeled), (η5-C6(CH3)5Re(NO)(PPh3)(C≡CSi(CH3)3) (86%), and (η5-C5(CH3)5)Re(NO)(PPh3)(C≡CSnPh3) (45%). © 1992, American Chemical Society. All rights reserved.

author list (cited authors)

  • Ramsden, J. A., Weng, W., & Gladysz, J. A.

citation count

  • 34

publication date

  • November 1992