Electrophile-induced cyclizations of chiral rhenium ethynyl and C[sub 2]Li complexes of the formula ([eta][sup 5]-C[sub 5]Me[sub 5])Re(NO)(PPh[sub 3]) (C[triple bond]CX). Synthesis, structure, and reactivity of unusual 1,3-dimetalated cyclic C[sub 4]H[sub 3] and C[sub 4]H[sub 4] species

Journal Article · Tue Jan 31 23:00:00 EST 1995 · Organometallics; (United States)

DOI:https://doi.org/10.1021/om00002a041· OSTI ID:6455790

Weng, W; Bartik, T; Johnson, M T; Arif, A M; Gladysz, J A ^[1]

---

1. Univ. of Utah, Salt Lake City, UT (United States)

Reactions of ([eta][sup 5]-C[sub 5]Me[sub 5])Re(NO)(PPh[sub 3])(C=CH) (1) or ([eta][sup 5]-C[sub 5]Me[sub 5])Re(NO)(PPh[sub 3])(C[triple bond]CL) (2) and ZnCl[sub 2] ([ge] 1.2 eqiv) give the meso dirhenium complex (SR,RS)-[([eta][sup 5]-C[sub 5]Me[sub 5])Re(NO)(PPh[sub 3]) (=C=CH=C(CH[sub 2])=)(Ph[sub 3]P)(ON)Re([eta][sup 5]-C[sup -5]Me[sub 5])] [sup +]([Zn[sub 2]Cl[sub 6]][sup 2])[sub [1/2]] (4). Samples contain up to 10% of the corresponding dl diastereomer (total yield 94-38%). Mechanisms involving adventitious water and initial electrophilic attack upon C[sub [beta]] of I are proposed. Accordingly, addition of 0.5 equiv of HBF[sub 4]-OEt[sub 2] to 1 (CH[sub 2]Cl[sub 2], 25[degree]C) gives the analogous dirhenium tetrafluroborate salt 5 (85%). However, addition of 1 to 2.0 equiv of HBF[sub 4]-OEt[sub 2] (THF, [minus]80[degree]C) gives the vinylidine complex [([eta][sup 5]-C[sub 5]Me[sub 5])Re(NO)(PPh[sub 3]) (=C=CH[sub 2])][sup +]BF[sub 4][sup -] (6; 86%). Reaction of 1 and 6 (CH[sub 2]Cl[sub 2], 25[degree]C) also gives 5 (94%). The crystal structure of 4 shows rhenium-carbon bonds of 2.00(1)-2.03(1) A, intermediate between single and double bonds and consistent with a delocalized structure based upon Re=C=CHC(CH[sub 2])=Re[sup +] resonance forms. NMR data establish 12.1-12.6 kcal/mol Re=C rotational barriers. 32 refs., 3 figs., 3 tabs.

• OSTI ID: 6455790
• Journal Information: Organometallics; (United States), Journal Name: Organometallics; (United States) Vol. 14:2; ISSN ORGND7; ISSN 0276-7333
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201* -- Chemical & Physicochemical Properties
BOND ANGLE
BOND LENGTHS
CHEMICAL REACTIONS
COMPLEXES
CRYSTAL STRUCTURE
DATA
DIMENSIONS
INFORMATION
INFRARED SPECTRA
LENGTH
LITHIUM COMPLEXES
MOLECULAR STRUCTURE
NMR SPECTRA
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
RHENIUM COMPLEXES
SPECTRA
SYNTHESIS
TRANSITION ELEMENT COMPLEXES