Illustration of all species and all microspecies involved in full protonation steps of spermine and determination of corresponding most abundant and most stable conformers, a gas phase theoretical study

Salehzadeh, Sadegh; Yaghoobi, Fereshteh; Bayat, Mehdi

doi:10.1016/j.chemphys.2009.05.002

Cited by 9 publications

(27 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As we mentioned above, the most stable complex, [Cu(tren)] 21 , has smallest proton macroaffinity and least stable one, [Cu(ppb)] 21 , has greatest proton macroaffinity. Obviously, if there is a good correlation between the proton macroaffinity of [M(L)] 21 complexes with their formation constants, then we Fig. 4).…”

Section: Proton Affinities and Formation Constantsmentioning

confidence: 89%

“…18,19,20,39 2. As can be seen in Table 1, the smallest proton macroaffinity (and also macrobasicity) is calculated for the [Cu(tren)] 21 . In fact, the order of the first proton macroaffinity and macrobasicity for the Cu 21 21 (i.e., completely opposite to the observed trend for their proton macroaffinity and macrobasicity).…”

Section: Proton Affinities and Formation Constantsmentioning

confidence: 99%

“…As can be seen in Table 1, the smallest proton macroaffinity (and also macrobasicity) is calculated for the [Cu(tren)] 21 . In fact, the order of the first proton macroaffinity and macrobasicity for the Cu 21 21 (i.e., completely opposite to the observed trend for their proton macroaffinity and macrobasicity). The latter observation once again confirms our assumption that there is a correlation between the proton affinity and basicity of a complex and its stability constant.…”

Section: Proton Affinities and Formation Constantsmentioning

confidence: 99%

“…Then, we show that the correct formulation of these complexes and their protonated form in solution is as [Cu(L)(H 2 O)] 21 and [Cu(HL)(H 2 O) 2 ] 31 , respectively. Thus, along with protonation of these complexes in solution one molecule of the solvent can be coordinated to the metal ion (see Fig.…”

Section: Introductionmentioning

confidence: 99%

“…[16][17][18][19][20][21] Very recently, we showed that the study on proton affinities of polybasic molecules at gas phase is useful for under-standing their structures in solution. 20,21 In this work, we want to show that such studies may also be useful for understanding the structure of metal complexes in solution. We report a theoretical study on the structure and proton affinity as well as basicity of Cu(II) complexes of a number of tripodal tetraamines in both the gas phase and solution (see Fig.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Theoretical studies on the structure and protonation of Cu(II) complexes of a series of tripodal aliphatic tetraamines: Good correlations with the experimental data

Salehzadeh

Bayat

2010

J Comput Chem

Self Cite

View full text Add to dashboard Cite

DFT(B3LYP) studies on first protonation step of a series of Cu(II) complexes of some tripodal tetraamines with general formula N[(CH(2))(n)NH(2)][(CH(2))(m)NH(2)][(CH(2))(p)NH(2)] (n = m = p = 2, tren; n = 3, m = p = 2, pee; n = m = 3, p = 2, ppe; n = m = 3, tpt; n = 2, m = 3, p = 4, epb; and n = m = 3, p = 4; ppb) are reported. First, the gas-phase proton macroaffinity of all latter complexes was calculated with considering following simple reaction: [Cu(L)](2+)(g) + H(+)(g) --> [Cu(HL)](3+)(g). The results showed that there is a good correlation between the calculated proton macroaffinities of all complexes with their stability constants in solution. Then, we tried to determine the possible reliable structures for microspecies involved in protonation process of above complexes. The results showed that, similar to the solid state, the [Cu(L)(H(2)O)](2+) and [Cu(HL)(H(2)O)(2)](3+) are most stable species for latter complexes and their protonated form, respectively, at gas phase. We found that there are acceptable correlations between the formation constants of above complexes with both the -Delta E and -Delta G of following reaction: [Cu(L)(H(2)O)](2+)(g) + H(+)(g) + H(2)O(g) --> [Cu(HL)(H(2)O)(2)](3+)(g). The -Delta E of the latter reaction can be defined as a theoretically solvent-proton macroaffinity of reactant complexes because they have gained one proton and one molecule of the solvent. The unknown formation constant of [Cu(epb)](2+) complex was also predicted from the observed correlations. In addition, the first proton affinity of all complexes was studied in solution using DPCM and CPCM methods. It was shown that there is an acceptable correlation between the solvent-proton affinities of [Cu(L)(H(2)O)](2+) complexes with formation constants of [Cu(HL)(H(2)O)(2)](3+) complexes in solution.

show abstract

Section: Proton Affinities and Formation Constantsmentioning

confidence: 89%

Section: Proton Affinities and Formation Constantsmentioning

confidence: 99%

Section: Proton Affinities and Formation Constantsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Theoretical studies on the structure and protonation of Cu(II) complexes of a series of tripodal aliphatic tetraamines: Good correlations with the experimental data

Salehzadeh

Bayat

2010

J Comput Chem

Self Cite

View full text Add to dashboard Cite

show abstract

Prediction of microscopic protonation constants of polybasic molecules via computational methods: A complete microequilibrium analysis of spermine

Salehzadeh

Gholiee

Bayat

2010

Int J of Quantum Chemistry

Self Cite

View full text Add to dashboard Cite

For the first time, a simple methodology is reported for theoretical calculation of microscopic protonation constants of polybasic molecules in solution. Density functional theory study was used for complete microequilibrium analysis of spermine, H 2 N(CH 2 ) 3 NH(CH 2 ) 4 NH(CH 2 ) 3 NH 2 , a linear tetraamine with 16 known microspecies. A general thermodynamic cycle is proposed to calculate protonation microconstants of polybasic molecules using calculated micro-DG values in aqueous solution. The microscopic protonation constants were determined with considering both the most abundant and most stable conformers for all microspecies. The results show that the microscopic protonation constants derived from the most abundant conformers (i.e., linear conformers in which the intramolecular hydrogen bonding does not exist) are in good agreement with the corresponding available experimental data.

show abstract

Synthesis, characterization and theoretical study of a new asymmetrical tripodal amine containing morpholine moiety

Rezaeivala

Salehzadeh

Keypour

et al. 2016

Arabian Journal of Chemistry

View full text Add to dashboard Cite

Illustration of all species and all microspecies involved in full protonation steps of spermine and determination of corresponding most abundant and most stable conformers, a gas phase theoretical study

Cited by 9 publications

References 16 publications

Theoretical studies on the structure and protonation of Cu(II) complexes of a series of tripodal aliphatic tetraamines: Good correlations with the experimental data

Theoretical studies on the structure and protonation of Cu(II) complexes of a series of tripodal aliphatic tetraamines: Good correlations with the experimental data

Prediction of microscopic protonation constants of polybasic molecules via computational methods: A complete microequilibrium analysis of spermine

Synthesis, characterization and theoretical study of a new asymmetrical tripodal amine containing morpholine moiety

Contact Info

Product

Resources

About