Hydrodesulfurization of organosulfur heterocycles by metal hydride-nickel(0) complexes: accelerated single-electron transfer in carbon-sulfur bond cleavage

Journal Article · Wed Nov 26 04:00:00 EST 1986 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00284a045· OSTI ID:7032786

Eisch, J J; Hallenbeck, L E; Han, K I

The novel nickel complex, LiAlH/sub 2/(THF)/sub n/ x C/sub 10/H/sub 8/N/sub 2/ x Ni (2), which results from the interaction in a THF solution of (2,2'-bipyridyl)(1,5-cyclooctadiene)nickel (1) with LiAlH/sub 4/ in a 1:1 molar ratio is a powerful desulfurizing agent in homogeneous solution for such aromatic sulfur hetercycles as dibenzothiophene (3), phenoxathiin (11), phenothiazine (12), and thianthrene (13). When employed in a 2:1 molar ratio with the heterocyclic substrate, 2 produces the corresponding ring-opened desulfurization products (biphenyl, diphenyl ether, diphenylamine, and benzene, respectively) in high yields. In contrast, 1 effects predominantly ring contraction during desulfurization and yields dibenzofuran, carbazole, and dibenzothiophene from 11, 12, and 13, respectively. From considerations of relative desulfurization rates for substituted dibenzothiphenes, deuterium labeling experiments, and the chemical reactivity differences for 1 and 2, it is concluded that these reagents desulfurize via single-electron-transfer mechanisms and that radical anions are crucial reactive intermediates. The greater reactivity of 2 is ascribed to its anionic nickel character.

• Research Organization: State Univ. of New York, Binghamton
• DOE Contract Number: FG22-81PC40782; FG22-84PC70786
• OSTI ID: 7032786
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 108:24; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ANIONS
AZINES
CHARGED PARTICLES
CHEMICAL BONDS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COMPLEXES
DATA
DESULFURIZATION
DEUTERIUM COMPOUNDS
ELECTRON TRANSFER
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
IONS
LABELLED COMPOUNDS
NICKEL COMPLEXES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PHENOTHIAZINES
RADICALS
REACTION INTERMEDIATES
THIONAPHTHENES
TRANSITION ELEMENT COMPLEXES
YIELDS