THESIS
2014
iii leaves, iv-xix, 179 pages : illustrations ; 30 cm
Abstract
A synthetic method for the preparation of rhenium alkyne complexes was developed.
Treatment of (O
2CMe)Re(CO)(PPh
3)
3 with terminal alkynes produces rhenium alkyne
complexes (O
2CMe)Re(CO)(PPh
3)
2(η
2-HC≡CR) (R = Ph, n-Bu, CO
2Et, C(Ph)
2OH). When
internal alkyne EtO
2CC≡CCO
2Et was used, the reaction produces a similar η
2-alkyne
complex (O
2CMe)Re(CO)(PPh
3)
2(η
2-EtO
2CC≡CCO
2Et).
Protonation of these rhenium alkyne complexes was investigated. Treatment of
(O
2CMe)Re(CO)(PPh
3)
2(η
2-HC≡CR) with HCl gives the rhenium η
2-vinyl complexes
ReCl
2(CO)(PPh
3)
2(η
2-H
2C=CR) (R = Ph, n-Bu) via the intermediates
ReCl(CO)(PPh
3)
2(η
3-MeCO
2C(R)=CH
2). Through a similar procedure, treatment of
(O
2CMe)Re(CO)(PPh
3)
2(η
2-EtO
2CC≡CCO
2Et) with HCl gives the rhenium alkene complex
ReCl(CO)(PPh
3)
2(η
3-MeCO
2C(CO
2Et)=CH-CO...[
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A synthetic method for the preparation of rhenium alkyne complexes was developed.
Treatment of (O
2CMe)Re(CO)(PPh
3)
3 with terminal alkynes produces rhenium alkyne
complexes (O
2CMe)Re(CO)(PPh
3)
2(η
2-HC≡CR) (R = Ph, n-Bu, CO
2Et, C(Ph)
2OH). When
internal alkyne EtO
2CC≡CCO
2Et was used, the reaction produces a similar η
2-alkyne
complex (O
2CMe)Re(CO)(PPh
3)
2(η
2-EtO
2CC≡CCO
2Et).
Protonation of these rhenium alkyne complexes was investigated. Treatment of
(O
2CMe)Re(CO)(PPh
3)
2(η
2-HC≡CR) with HCl gives the rhenium η
2-vinyl complexes
ReCl
2(CO)(PPh
3)
2(η
2-H
2C=CR) (R = Ph, n-Bu) via the intermediates
ReCl(CO)(PPh
3)
2(η
3-MeCO
2C(R)=CH
2). Through a similar procedure, treatment of
(O
2CMe)Re(CO)(PPh
3)
2(η
2-EtO
2CC≡CCO
2Et) with HCl gives the rhenium alkene complex
ReCl(CO)(PPh
3)
2(η
3-MeCO
2C(CO
2Et)=CH-CO
2Et). The η
2-vinyl complex was not obtained
through this reaction.
A synthetic method for the preparation of osmium dioxygen complexes was developed.
Treatment of (C
5Me
4R)Os(PPh
3)
2Cl with TlOTf under air gives the osmium dioxygen
complexes [(C
5Me
4R)Os(O
2)(PPh
3)
2]OTf (R = H, Me, Et, n-Pr). New osmium cyclometalated
products [(C
5Me
4R)OsH(PPh
3)(η
2-2-C
6H
4PPh
2)]OTf (R = H, Me, Et) were produced when
the reactions were carried out under nitrogen.
Catalytic Kharasch addition reactions between selected halogenated compounds and
olefins were studied. Heating a mixture of halogenated compounds and olefins at 60 ℃ in the
presence of 3 mol % of [(C
5Me
4R)Os(O
2)(PPh
3)
2]OTf or (C
5Me
4R)Os(PPh
3)
2Cl gives
anti-Markovnikov adducts. (C
5Me
4R)Os(PPh
3)
2Cl shows better catalytic ability. Aromatic
olefins are generally favorable substrates in this reaction. CCl
4 and CHBr
3 are found to be
reactive halogenated species.
Reactions of terminal alkynes and alkynols catalyzed by ruthenium complexes were
studied. The steric bulkiness of the ligands may enhance Z-isomer selectivity in dimerization
reactions. The reaction of alkynols catalyzed by [Ru(OAc)(NP
3)]BPh
4 (NP
3 =
tris[2-(diphenylphosphino)phenyl]methanamine)) give dimeric species, rather than endo-enol
ether as the major product.
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