6343-54-0Relevant articles and documents
A Mild and Efficient Preparation of cis-1,2-Diols from 1,2,4-Trioxanes
Jefford, Charles W.,Rossier, Jean-Claude,Boukouvalas, John
, p. 1593 - 1594 (1987)
3,3-Unsubstituted cis-fused bicyclic 1,2,4-trioxanes, on treatment with benzylamine, gave the corresponding cis-1,2-diols in 85-99percent yield.
A formylating agent by dehydration of the natural product DIMBOA
Hofmann, Angelika,Sicker, Dieter
, p. 1151 - 1153 (1999)
The natural aglucone 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA, 1) of maize underwent spontaneous dehydration and rearrangement to form 3-formyl-6-methoxybenzoxazolin-2(3H)-one (FMBOA, 2) on reaction with N- ethoxycarbonyl-trichloroacetaldimine. Compound 2 was proven to be a reactive formyl donor toward N-, O-, and S-nucleophiles, which may be important in case 2 is formed under biological conditions.
Modulation by Amino Acids: Toward Superior Control in the Synthesis of Zirconium Metal–Organic Frameworks
Gutov, Oleksii V.,Molina, Sonia,Escudero-Adán, Eduardo C.,Shafir, Alexandr
, p. 13582 - 13587 (2016)
The synthesis of zirconium metal–organic frameworks (Zr MOFs) modulated by various amino acids, including l-proline, glycine, and l-phenylalanine, is shown to be a straightforward approach toward functional-group incorporation and particle-size control. High yields in Zr-MOF synthesis are achieved by employing 5 equivalents of the modulator at 120 °C. At lower temperatures, the method provides a series of Zr MOFs with increased particle size, including many suitable for single-crystal X-ray diffraction studies. Furthermore, amino acid modulators can be incorporated at defect sites in Zr MOFs with an amino acid/ligand ratio of up to 1:1, depending on the ligand structure and reaction conditions. The MOFs obtained through amino acid modulation exhibit an improved CO2-capture capacity relative to nonfunctionalized materials.
Dehydrogenative Synthesis of Carbamates from Formamides and Alcohols Using a Pincer-Supported Iron Catalyst
Bernskoetter, Wesley H.,Hazari, Nilay,Mercado, Brandon Q.,Townsend, Tanya M.
, p. 10614 - 10624 (2021/09/02)
We report that the pincer-ligated iron complex (iPrPNP)Fe(H)(CO) [1, iPrPNP- = N(CH2CH2PiPr2)2-] is an active catalyst for the dehydrogenative synthesis of N-alkyl- and N-aryl-substituted carbamates from formamides and alcohols. The reaction is compatible with industrially relevant N-alkyl formamides, as well as N-aryl formamides, and 1°, 2°, and benzylic alcohols. Mechanistic studies indicate that the first step in the reaction is the dehydrogenation of the formamide to a transient isocyanate by 1. The isocyanate then reacts with the alcohol to generate the carbamate. However, in a competing reaction, the isocyanate undergoes a reversible cycloaddition with 1 to generate an off-cycle species, which is the resting state in catalysis. Stoichiometric experiments indicate that high temperatures are required in catalysis to facilitate the release of the isocyanate from the cycloaddition product. We also identified several other off-cycle processes that occur in catalysis, such as the 1,2-addition of the formamide or alcohol substrate across the Fe-N bond of 1. It has already been demonstrated that the transient isocyanate generated from dehydrogenation of the formamide can be trapped with amines to form ureas and, in principle, the isocyanate could also be trapped with thiols to form thiocarbamates. Competition experiments indicate that trapping of the transient isocyanate with amines to produce ureas is faster than trapping with an alcohol to produce carbamates and thus ureas can be formed selectively in the presence of alcohols. In contrast, thiols bind irreversibly to the iron catalyst through 1,2 addition across the Fe-N bond of 1, and it is not possible to produce thiocarbamates. Overall, our mechanistic studies provide general guidelines for facilitating dehydrogenative coupling reactions using 1 and related catalysts.
Catalysis of Positively Charged Ru Species Stabilized by Hydroxyapatite in Amine Formylation
Jiao, Dongxia,Wang, Yehong,Zhang, Zhixin,Zhang, Jian,Lei, Lijun,Wang, Feng
, p. 4159 - 4163 (2021/08/20)
Formamide is an important solvent and synthetic intermediate. Herein, we designed a hydroxyapatite (HAP)-stabilized, positively charged Ru-based catalysts which can efficiently catalyze the formylation reaction of amines with CO for the synthesis of formamide. The Ru-HAP showed excellent catalytic performance in N,N-Dimethylformamide (DMF) synthesis, with about 75 % dimethylamine conversion and >99 % DMF selectivity at 300 h of continuous reaction. The combination of characterization results and control experiments showed that positively charged Ru species, including hydrated RuOx and Ru3+ species, were catalytically active. In particular, the surface RuOx species were more active than the Ru3+ species located within the HAP framework.
