메뉴 건너뛰기




Volumn 64, Issue 6, 1999, Pages 1843-1848

Stereospecific and regioselective isocyanide insertions into siliranes and reactions of the resulting iminosilacyclobutanes

Author keywords

[No Author keywords available]

Indexed keywords

CYANIDE; CYCLOBUTANE DERIVATIVE; HETEROCYCLIC COMPOUND; IMINOSILACYCLOBUTANE; SILIRANE; UNCLASSIFIED DRUG;

EID: 0033583141     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo9816257     Document Type: Article
Times cited : (28)

References (31)
  • 17
    • 0345353459 scopus 로고    scopus 로고
    • note
    • 29Si NMR chemical shifts of 2 and 3 correlate to stereochemistry: the two cis products cis-2 and cis-3 have chemical shifts of 31.4 and 31.5 ppm, respectively, whereas the two trans products trans-2 and trans-3 have chemical shifts of 30.2 and 30.6 ppm, respectively.
  • 18
    • 0344491037 scopus 로고    scopus 로고
    • note
    • These results are in contrast to the one-or two-atom insertions of sulfur into silacyclopropanes 1, which are not stereospecific. Radical intermediates were suggested for those transformations (ref 9).
  • 20
    • 0344059804 scopus 로고    scopus 로고
    • note
    • The stereochemistry about the imine is not known. Weidenbruch, in his studies of this reaction (ref 5), demonstrated by X-ray crystallography that an iminosilacyclobutane possessed the (Z)-stereochemistry.
  • 21
    • 0345353458 scopus 로고    scopus 로고
    • note
    • We have examined the relative energies of the imine form and enamine form computationally using ab initio methods (the Spartan program from Wavefunction, Inc., Irvine, CA was employed). These calculations indicate that the relative energies between the two forms depends on the level of substitution on the silicon and nitrogen atoms as well as the substitution on the two ring carbons. Therefore, we conclude that the driving force behind the tautomerization is steric in origin.
  • 24
    • 0344922101 scopus 로고    scopus 로고
    • note
    • 1H NMR spectroscopy and gas chromatography. This small amount of trans-dimethyl compound is most likely due to the presence of trans-2-butene as an impurity in commercially available cis-2-butene, from which silacyclopropane cis-1 was made. The typical purity of cis-1 is ≥95%.
  • 27
    • 0344491034 scopus 로고    scopus 로고
    • note
    • Homonuclear NOE experiments on 16 reveal a large NOE between the tert-butyl imino group and the C-4 methine and the hydroxyl group. These data are consistent with a conformation with both methyl groups and the trifluoromethyl group in axial positions, presumably to alleviate allylic strain.
  • 28
    • 0344922099 scopus 로고    scopus 로고
    • note
    • 2 provided 10 and 11 in 66% overall yield from cis-3.
  • 31
    • 0344922097 scopus 로고    scopus 로고
    • note
    • Repeated attempts to obtain satisfactory elemental analysis were unsuccessful. Silicon carbide formation could prevent proper analyses.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.