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 · Wed Feb 01 00:00:00 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]

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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), Vol. 14:2; ISSN 0276-7333
• Country of Publication: United States
• Language: English

Related Subjects

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