Phospha-munchnones: electronic structures and 1,3-dipolar cycloadditions

St-Cyr, Daniel J., Morin, Marie S. T., Belanger-Gariepy, Francine, Arndtsen, Bruce A., Krenske, Elizabeth H. and Houk, K. N. (2010) Phospha-munchnones: electronic structures and 1,3-dipolar cycloadditions. Journal of Organic Chemistry, 75 12: 4261-4273. doi:10.1021/jo1008383

Author St-Cyr, Daniel J.
Morin, Marie S. T.
Belanger-Gariepy, Francine
Arndtsen, Bruce A.
Krenske, Elizabeth H.
Houk, K. N.
Title Phospha-munchnones: electronic structures and 1,3-dipolar cycloadditions
Formatted title
Phospha-münchnones: electronic structures and 1,3-dipolar cycloadditions
Journal name Journal of Organic Chemistry   Check publisher's open access policy
ISSN 0022-3263
Publication date 2010-06-01
Year available 2010
Sub-type Article (original research)
DOI 10.1021/jo1008383
Open Access Status
Volume 75
Issue 12
Start page 4261
End page 4273
Total pages 13
Place of publication Washington, United States
Publisher American Chemical Society
Language eng
Formatted abstract
The reaction of imines, acid chlorides, PR3, and base generates a new class of 1,3-dipoles: phospha-Münchnones. These 1,3-dipoles can undergo cycloadditions with alkynes followed by loss of phosphine oxides to form pyrroles. Cycloaddition reactivity is dependent upon the PR3 employed, with PhP(catechyl) (catechyl = o-O2C6H4) providing the most rapid cycloadditions and optimal pyrrole yields. 1H, 13C, and 31P NMR analysis and computations indicate that electron-poor catechyl-substituted phosphonites and phosphites favor a cyclic 1,3-dipolar structure, while more electron-rich phosphines instead favor the valence tautomeric acyclic ylides. X-ray crystallographic studies confirm this. Density functional theory calculations support the wide variety of P−O interactions induced by different PR3 groups and indicate that the most efficient concerted 1,3-dipolar cycloadditions are those for dipoles whose ground-state geometry is most like the transition-state geometry. Reactions of these dipoles with monosubstituted alkynes bearing an electron-withdrawing group are calculated to occur by stepwise mechanisms. The presence of the phosphorus unit creates a large electronic bias across the 1,3-dipole, allowing for regioselective cycloadditions with substituted alkynes.
Keyword Amino acid derivatives
Wittig type reaction
Hexacoordinate phosphorus
Pyrrole Synthesis
Stereoselective synthesis
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: School of Chemistry and Molecular Biosciences
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 28 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 33 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Sat, 02 Mar 2013, 06:29:20 EST by System User on behalf of Scholarly Communication and Digitisation Service