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Research was conducted to examine the reactivities of organozinc derivatives to reactions such as Michael addition, carbozincation, epoxide ring opening and halogen-zinc exchange. The derivatives were prepared in situ using lithium thiocyanate, lithium cyanide and methyllithium. Results show the high and unique reactivity of the organozincates compared with triorganozincates. This indicates that the derivatives can be classified under a new category of zincate species.

The Dialkylzinc hydride ate complexes generated in situ from dialkylzinc and metal hydride were examined to determine their design, reactivities and practical application. Results indicated that dimethylzinc hydrides are the most powerful and selective zincates for the reduction of the carbonyl group. There are also various reactivities of dialkylzinc hydride 'ate' complexes.

A novel method of synthesizing indoles containing substituents at the benzene moiety was developed through a combined process of directed ortho-lithiation and indole cyclization reaction. The design featured the use of hydrooxyindole-induced conversion and palladium-catalyzed reaction. 1-(tert-butoxycarbonyl) indole was used as an intermediate during the indole cyclization.

The deallylation of allyl aryl ethers using a highly reactive electrochemically generated nickel is described. Highly reactive nickel was easily prepared by electrolysis in a DMF solution. The reaction proceeded in good yields in the presence of NaOAc under mild conditions without any effect on the various functional groups. Moreover, the deallylation was not affected by other O-protecting groups including the benzyl, tosyl and tetrahydropyranyl groups.

A study was conducted to analyze the reduction of nitrobenzenes to anilines by electrogenerated nickel at room temperature in a short time without influencing different functional groups. The Jasco IR-810 spectrophotometer was utilized to obtain infrared spectra. Results indicated that the reduction of nitrobenzenes to anilines proceeds under mild conditions and that no co-reducing agents or hydrogen gas were needed.

Diastereoselective Birch reduction-alkylation reactions of bicyclic [beta]-alkoky-[alpha],[beta]-unsaturated carbonyl compounds and tricyclic analogues are examined. The product from the tricyclic [beta]-alkoxy-[alpha],[beta]-unsaturated carbonyl compound has corresponded to the trichothecene skeleton.

New methods are described for preparing functionalized benzynes with lithium di-alkyl(2,2,6,6-tetramethylpiperidino)zincate ([R.sub.2]Zn(TMP)Li) through deprotonative zincation as a key reaction. The results haves shown that preferential coordination of the dialkylzinc moiety of zincate to halogen is the reason for the reduced activation energy of the elimination or for the formation of the benzyne.

A catalytic electron transfer (ET) system consisting of a transition metal ate complex (Me(sub 3)M(II)Li) and magnesium is developed. The ET capacity of this system can be tuned by altering the ligands of the ate complexes and applied to representative organic changes involving anion radicals.

The development of efficient methods for the indole synthesis catalyzed by Cu(II) salts and its applications is investigated. Cu(OAc)2 is proved to be the best catalyst for the synthesis of various 1-polysulfonyl or 1-methylsulfonylindoles, which have both electron-withdrawing and electron-donating groups on the aromatic ring and C2 position of indoles.

The report stated several methods for generating functionalized benzynes bearing restricted substituents such as alkyl, alkoxy or halogen groups. The report concluded that a chemo-/regioselective directed zincation of metafunctionlized haloaromtics and a versatile generation of 3-substituted benzynes could be achieved by utilizing the drastic ligand effects in zincates.

The novel deprotonative zincation of functionalized aromatics and heteroaromatics using di-tert-butyltetramethylpiperidinozincate (TMP-zincate) was investigated. The complex showed different signals in the spectra from that of lithium tetramethylpiperidide or di-tert-butylzinc (2'BuLi + ZnCl2), suggesting the formation of the new ate complex. After observing the spectra for several hours at room temperature, no decomposition was noted.

Triorganozincates are versatile reagents in the construction of carbon-carbon bonds, and for the metaliation of aromatic halides or vinyl halides. Evidence is presented to support the existence of 'highly coordinated zincates, tetracoordinated dianionic ZN(II) species, through the use of H NMR, Raman spectrosocpy and extended X-ray absorption fine structure (EXAFS) studies.

The reactivity of tetraalkylorganozincates and related modified organozincates was investigated. 1H NMR study of organozincates showed a difference between these highly coordinated zincates and lithium trimethylzincate. A comparison of the reactivity of these reagents revealed a different regioselectivity for epoxide opening and a different reactivity toward halogen-metal exchange. A distinction in structure and reactivity between these zincates and ordinary lithium trialkylzincates is thus deemed imperative.

A halogen-exchange reaction between aromatic halides and lithium trialkylzincates produces lithium aryldimethylzincates. A study of the reactions between various electrophiles and zincates produced from p-iodoanisole helps determine the reactivity of lithium aryldimethylzincates. Zincates exhibit efficient 1,2-addition reactions and the halogen-zinc exchange reaction is compatible with different functional groups.