Iodine-Catalyzed Synthesis of N,N′-Chelate Organoboron Aminoquinolate
摘要:
We disclose a novel method for the synthesis of fluorescent N, N'-chelate organoboron compounds in high efficiency by treatment of aminoquinolates with NaBAr4/R'COOH in the presence of an iodine catalyst. These compounds display high air and thermal stability. A possible catalytic mechanism based on the results of control experiments has been proposed. Fluorescence quantum yield of 3b is up to 0.79 in dichloromethane.
Synthesis and Characterization of Dialkylaluminum Amidates and Their Ring-Opening Polymerization of ε-Caprolactone
摘要:
The stoichiometric reactions of N-(2-methylquinolin-8-yl) (R)amides (L1-L8; L1, R = Ph; L2, R = p-FPh; L3, R = p-ClPh; L4, R = p-(MeO)Ph; L5, R = o-MePh; L6, R = p-MePh; L7, R = Me; L8, R = CF3) with Me3Al afforded the corresponding dimethylaluminum amidate complexes [Me2AlL] (C1-C8). The treatment of N-(2-methylquinolin-8-yl)picolinamide (L9) with 1 or 2 equiv of Me3Al formed Me(2)AlL9 (C9) or Me(2)AlL9 center dot Me(3)A1 (C10), respectively; meanwhile, the stoichiometric reaction of L9 with iBu(3)Al gave iBu(2)AlL9 (C11). All organoaluminum amidate complexes were fully characterized by H-1/C-13 NMR spectroscopy and elemental analysis, and the unambiguous structures of complexes C2, C4, C9, and C11 were further determined by single-crystal X-ay diffraction. With the assistance of 1 equiv of BnOH, all dialkylaluminum amidate complexes showed appreciable activities toward the ring-opening polymerization of epsilon-caprolactone and produced polycaprolactones with narrow polydispersity; the nature of the active species was also investigated.
The reaction of trifluoroacetyl amides with Grignard reagent for the substitution of CF3 group with various alkyl or arylgroups is described. A variety of aryl, quinolin-8-yl, and (hetero)alkyl functional groups as well as F, Cl, and Br atoms are well tolerated. These moisture-stable and easily available trifluoroacetyl amides can be conveniently obtained and used as new versatile precursors for isocyanates
We disclose a novel method for the synthesis of fluorescent N, N'-chelate organoboron compounds in high efficiency by treatment of aminoquinolates with NaBAr4/R'COOH in the presence of an iodine catalyst. These compounds display high air and thermal stability. A possible catalytic mechanism based on the results of control experiments has been proposed. Fluorescence quantum yield of 3b is up to 0.79 in dichloromethane.
Synthesis and Characterization of Dialkylaluminum Amidates and Their Ring-Opening Polymerization of ε-Caprolactone
作者:Wenjuan Zhang、Youhong Wang、Ji Cao、Lin Wang、Yi Pan、Carl Redshaw、Wen-Hua Sun
DOI:10.1021/om2008343
日期:2011.11.28
The stoichiometric reactions of N-(2-methylquinolin-8-yl) (R)amides (L1-L8; L1, R = Ph; L2, R = p-FPh; L3, R = p-ClPh; L4, R = p-(MeO)Ph; L5, R = o-MePh; L6, R = p-MePh; L7, R = Me; L8, R = CF3) with Me3Al afforded the corresponding dimethylaluminum amidate complexes [Me2AlL] (C1-C8). The treatment of N-(2-methylquinolin-8-yl)picolinamide (L9) with 1 or 2 equiv of Me3Al formed Me(2)AlL9 (C9) or Me(2)AlL9 center dot Me(3)A1 (C10), respectively; meanwhile, the stoichiometric reaction of L9 with iBu(3)Al gave iBu(2)AlL9 (C11). All organoaluminum amidate complexes were fully characterized by H-1/C-13 NMR spectroscopy and elemental analysis, and the unambiguous structures of complexes C2, C4, C9, and C11 were further determined by single-crystal X-ay diffraction. With the assistance of 1 equiv of BnOH, all dialkylaluminum amidate complexes showed appreciable activities toward the ring-opening polymerization of epsilon-caprolactone and produced polycaprolactones with narrow polydispersity; the nature of the active species was also investigated.