Karplus‐Type Dependence of Vicinal 119Sn‐13C and 119Sn‐1H Spin‐Spin Couplings in Organotin(IV) Derivatives: A DFT Study

Casella, Girolamo; Ferrante, Francesco; Saielli, Giacomo

doi:10.1002/ejoc.200900197

Cited by 14 publications

(16 citation statements)

References 47 publications

(68 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[7a] Interestingly, yields were found to be higher when reactions were carried out in benzene instead of cyclohexane which is most likely due to the higher solubility of N ‐protected β‐amino alcohols 2 in such solvent (65 % compared to 45 % for 3a , Table , Entries 1 and 2; and 79 % compared to 61 % for 3c , Table , Entries 4 and 5). The assignment of the trans or cis configuration was unambiguously obtained on the basis of 3 J Sn‐C‐Z‐C , 3 J H‐H , 2 J Sn‐H and δ H2 values for the oxazolidine NMR spectra; these agreed well with our previous work and with theoretical studies reported for the evaluation of 3 J Sn‐C‐Z‐C . Furthermore, these assignments were corroborated by NOESY experiments.…”

Section: Resultssupporting

confidence: 89%

Stereoselective Synthesis of Stannylated Dehydropiperidines and Dehydroazepanes

et al. 2016

View full text Add to dashboard Cite

An efficient allylation and butenylation of N‐alkoxycarbonyl‐2‐tributylstannyl‐1,3‐oxazolidines derived from (S)‐vinylglycinol or (S)‐styrylglycinol is described. After conversion of the stannylated azadienes into stannylated dienyl oxazolidinones, a ring‐closing metathesis generates dehydropiperidine or dehydroazepane; both are interesting scaffolds for the synthesis of polyfunctionnalized piperidines or azepanes. Whereas the dehydropiperidine synthesis was found to be selective regardless of the Grubbs catalyst used, we found that Grubbs II catalyst induced partial double bond isomerization in the dehydroazepane series. In addition, when allyltrimethylsilane was used in the ring‐opening reactions of N‐alkoxycarbonyl‐2‐tributylstannyl‐1,3‐oxazolidines, cyclopropyl derivatives were selectively obtained.

show abstract

Section: Resultssupporting

confidence: 89%

Stereoselective Synthesis of Stannylated Dehydropiperidines and Dehydroazepanes

et al. 2016

View full text Add to dashboard Cite

show abstract

“…The perfect correlation of Sn, 1 H) in organotin(IV) derivatives with dihedral angles described by empirical Karplus-type equations are validated by DFT methods at both the non-relativistic and scalar ZORA relativistic levels. [107] Concerning 3 J( 119 Sn, 13 C) the relativistic protocol gives results which are in excellent agreement with the experimental coupling constants. Furthermore, it has also been reported that the electron-withdrawing strength of the N-substituents strongly affects the magnitude of the couplings and shape of the Karplus-type curve.…”

Section: Dft Calculationssupporting

confidence: 80%

Measurement and Applications of Long‐Range Heteronuclear Scalar Couplings: Recent Experimental and Theoretical Developments

2012

View full text Add to dashboard Cite

The use of long-range heteronuclear couplings, in association with (1)H-(1)H scalar couplings and NOE restraints, has acquired growing importance for the determination of the relative stereochemistry, and structural and conformational information of organic and biological molecules. However, the routine use of such couplings is hindered by the inherent difficulties in their measurement. Prior to the advancement in experimental techniques, both long-range homo- and heteronuclear scalar couplings were not easily accessible, especially for very large molecules. The development of a large number of multidimensional NMR experimental methodologies has alleviated the complications associated with the measurement of couplings of smaller strengths. Subsequent application of these methods and the utilization of determined J-couplings for structure calculations have revolutionized this area of research. Problems in organic, inorganic and biophysical chemistry have also been solved by utilizing the short- and long-range heteronuclear couplings. In this minireview, we discuss the advantages and limitations of a number of experimental techniques reported in recent times for the measurement of long-range heteronuclear couplings and a few selected applications of such couplings. This includes the study of medium- to larger-sized molecules in a variety of applications, especially in the study of hydrogen bonding in biological systems. The utilization of these couplings in conjunction with theoretical calculations to arrive at conclusions on the hyperconjugation, configurational analysis and the effect of the electronegativity of the substituents is also discussed.

show abstract

“…12 Recently, we reported on DFT calculations, at the relativistic and nonrelativistic levels, of the vicinal coupling constants for the same set of rigid compounds used by Kitching and Quintard to derive the corresponding Karplus-type equations. 13 The agreement with experimental data was very good. We also highlighted the strong influence of substituents and coupling paths on the value of the coupling constant which is, therefore, not dependent on the dihedral angle j only.…”

Section: Introductionsupporting

confidence: 61%

“…Early works, concerning the validation of Karplus-type equations involving tin in organotin(IV) derivatives, were carried out by Kitching and co-workers for 3 J( 119 Sn-C-C- 13 C), based on experimental couplings observed in a set of rigid polycyclic compounds, 9 and by Quintard and co-workers who derived analogous relationships for vicinal couplings between tin and deuterium, 3 J( 119 Sn-C-C-2 H). 10 This latter equation can be extended to tinproton couplings, 3 J( 119 Sn-C-C-1 H), by a simple conversion.…”

Section: Introductionmentioning

confidence: 99%

A DFT study of the Karplus-type dependence of vicinal 3J(Sn–C-X-C), X=N,O,S, in organotin(iv) compounds: application to conformationally flexible systems

2010

Self Cite

View full text Add to dashboard Cite

ZORA relativistic and non-relativistic DFT protocols have been used to investigate vicinal coupling constants, (3)J(Sn-C-X-C), in several organotin(iv) compounds, with particular emphasis on cyclic alpha-aminoorganostannanes. The dependence of the coupling constant on the heteroatom X (X = N,O,S) in the coupling path, and, for X = N, its substituents, has been studied in detail. The electron-withdrawing strength of the N-substituents has been found to strongly affect the magnitude and shape of the Karplus-type curve. The results obtained for the simple model systems, having no or little conformational flexibility, have helped in rationalizing the data concerning real flexible cyclic systems recently investigated in the literature. For these intricate cases a population analysis of various conformers has allowed to obtain a very good agreement between calculated and experimental data. It is therefore established that NMR J couplings, together with DFT calculations, are a very useful tool to investigate conformational issues in solution by comparison of experimental and weighted average calculated values.

show abstract

Karplus‐Type Dependence of Vicinal ¹¹⁹Sn‐¹³C and ¹¹⁹Sn‐¹H Spin‐Spin Couplings in Organotin(IV) Derivatives: A DFT Study

Cited by 14 publications

References 47 publications

Stereoselective Synthesis of Stannylated Dehydropiperidines and Dehydroazepanes

Stereoselective Synthesis of Stannylated Dehydropiperidines and Dehydroazepanes

Measurement and Applications of Long‐Range Heteronuclear Scalar Couplings: Recent Experimental and Theoretical Developments

A DFT study of the Karplus-type dependence of vicinal 3J(Sn–C-X-C), X=N,O,S, in organotin(iv) compounds: application to conformationally flexible systems

Contact Info

Product

Resources

About