Chemistry of ([eta][sup 5]:[eta][sup 5]-biphenyl)[Cr(CO)[sub 3]][sub 2] dianions. II. Two equivalent reduction of copper(I) salts. III. A new Rieke active copper: Reduction of a CuCN[center dot]nLiX complex

Miscellaneous · Wed Jan 01 00:00:00 EST 1992

OSTI ID:7069336

Dawson, B T

The dianion of the ([eta][sup 6] : [eta][sup 6]-biphenyl)[Cr(CO)[sub 3]][sub 2] complex reacted regioselectively with numerous electrophiles to form [[mu]-6-alkyl-6-([mu][sup 6]-phenyl)(1-5-[mu][sup 5])-cyclohexadienyl]-[Cr(CO)[sub 3]][sub 2] anion intermediates. The fate of the anion intermediates included: (1) direct oxidation and formation of 2-substituted biphenyls, (2) protonation, oxidation and the isolation of 5-alkyl-5-phenyl-1,3-cyclohexadienes, (3) nucleophilic attack on the ([eta][sup 6]-phenyl)Cr(CO)[sub 3] moiety, oxidation and formation of 2,4[prime]-disubstituted biphenyls, or (4) in the case where the initial electrophile contains an activated methylene unit, treatment with LDA, oxidation and the formation of ring annulation products. A second project involved the search for a copper anion. Reduction of CuI[center dot]PR[sub 3] complexes with two equivalents of lithium naphthalenide resulted in finding that as the reduction temperature of the Cu(I) salt decreased, reactivity of the copper towards oxidative addition to organic halides increased. One equivalent of alkyl or aryl bromide or chloride, reacted with one equivalent of copper after the copper was reduced at temperatures near the freezing point of THF. The CuCN[center dot]2LiBr complex was a satisfactory source of copper. Organocopper reagents containing ester, nitrile, and chloride functionalities were prepared and utilized in Michael reactions. The omission of phosphines allowed the ready isolation of products in high purity. The additions of allylic chlorides to the CuCN-based copper provided a convenient method of forming allylcopper reagents. Allylcopper reagents are difficult to prepare since most procedures suffer from homocoupling or involve preparations which call for transmetallation steps. Functionalized allylcopper reagents containing ester, nitriles, epoxides, and chlorides were prepared and reacted with acid chlorides, aldehydes and ketones.

• Research Organization: Nebraska Univ., Lincoln, NE (United States)
• OSTI ID: 7069336
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBONATES
CHEMICAL REACTIONS
CHROMIUM COMPLEXES
COPPER COMPLEXES
REDUCTION
ANIONS
BIPHENYL
ELECTROCHEMISTRY
ORGANOMETALLIC COMPOUNDS
STEREOCHEMISTRY
AROMATICS
CARBON COMPOUNDS
CHARGED PARTICLES
CHEMISTRY
COMPLEXES
HYDROCARBONS
IONS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
TRANSITION ELEMENT COMPLEXES
400400* - Electrochemistry
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