Synthesis of inherently chiral calix[4]arenes: Stereocontrol through ligand choice

Organic Letters

Volumn 12, Issue 20, 2010, Pages 4600-4603

  Herbert, Simon A ^a   Arnott, Gareth E ^a  

^a STELLENBOSCH UNIVERSITY   (South Africa)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 77957837044     PISSN: 15237060     EISSN: 15237052     Source Type: Journal    
DOI: 10.1021/ol101909f     Document Type: Article

References (55)

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23. Deconvolution performed using Kirk Marat's SPINWORKS 3.1.6 Software, University of Manitoba. Available from http://www.umanitoba.ca/chemistry/nmr/ spinworks.
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45. Using a conformationally restricted ferrocene oxazoline
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49. Monomer or triple ion transition states have been explored but seem to be dependent on the oxazoline used and the ligand's role; see ref 27.
50. At the RB3LYP/6-311G level of theory.
51. ΔΔ G = - RT ln([ 6a ]/[ 6b ]).
52. Substituents α to the nitrogen are known to dramatically slow down the ortholithiation step and have been shown to clash with ancillary (nonreacting) alkyllithium fragments or TMEDA in triple ion or monomer-based transition states respectively; see ref 27.
53. This is analogous to our previous work (ref 3) and to that of ref 26.
54. ‡.
55. After hydrolysis of the oxazoline; see ref 3.