Synthesis and structural investigation of internally coordinated alpha-amidoboronic acids.
[structure: see text] Six new N-acyl-boroGly derivatives, along with their N-acyl-boroSar analogues, have been synthesized by modification of conventional procedures. Structural characterization of these alpha-amidoboronic acids was accomplished by extensive use of 11B and 1H NMR spectroscopy. These compounds were prepared to determine the extent of intramolecular B-O dative bond formation within the context of a five-membered (:O=C-N-C-B) ring motif. It is shown that the formation of such dative bonds depends on the nature of the substituents at both the acyl carbon and the nitrogen atoms. Computational evidence from second-order Møller-Plesset perturbation theory is provided in support of these findings.
Lai
Jack H
JH
Department of Biochemistry, Tufts University School of Medicine, 136 Harrison Avenue, Boston, Massachusetts 02111, USA.
Liu
Yuxin
Y
Wu
Wengen
W
Zhou
Yuhong
Y
Maw
Hlaing H
HH
Bachovchin
William W
WW
Bhat
Krishna L
KL
Bock
Charles W
CW
D000577:Amides / Q000138:chemical synthesis / Q000737:chemistry*; D001897:Boronic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation
D000577:Amides; D001897:Boronic Acids