Asymmetric construction of quaternary stereocenters by magnesium catalysed direct amination of β-ketoesters using in situ generated nitrosocarbonyl compounds as nitrogen sources

2014 ◽  
Vol 5 (10) ◽  
pp. 3941-3945 ◽  
Author(s):  
Biplab Maji ◽  
Mahiuddin Baidya ◽  
Hisashi Yamamoto
Keyword(s):  
Nitrogen Sources ◽  
Magnesium Salt ◽  
Direct Amination ◽  
Quaternary Stereocenters

An oxophilic magnesium salt in combination with a chiral N,N′-dioxide ligand switches the chemoselectivity of an ambident nitrosocarbonyl species to nitrogen for the highly enantioselective α-amination of β-ketoesters.

ChemInform Abstract: Iron-Catalyzed Direct Amination of Azoles Using Formamides or Amines as Nitrogen Sources in Air.

ChemInform ◽  
2011 ◽  
Vol 42 (28) ◽  
pp. no-no
Author(s):  
Jian Wang ◽  
Ji-Ting Hou ◽  
Jun Wen ◽  
Ji Zhang ◽  
Xiao-Qi Yu
Keyword(s):  
Nitrogen Sources ◽  
Direct Amination

Construction of trifluoromethylated quaternary stereocenters via p-quinone methides

2020 ◽  
Vol 56 (20) ◽  
pp. 3031-3034 ◽  
Author(s):  
Kyu Terashima ◽  
Tomoko Kawasaki-Takasuka ◽  
Tomohiro Agou ◽  
Toshio Kubota ◽  
Takashi Yamazaki
Keyword(s):  
Synthetic Method ◽  
Quinone Methides ◽  
Quaternary Centers ◽  
Quaternary Stereocenters

Development of a new synthetic method for the construction of quaternary centers with a CF3 group was realized by way of 1,6-addition of various nucleophiles to highly reactive δ-trifluoromethylated p-quinone methides generated in situ.

Generation of azaarene nitrile oxides from methyl azaarenes and t-BuONO enabling synthesis of furoxans and 1,2,4-oxadiazoles

2022 ◽  
Author(s):  
Xiang-Jin Zhang ◽  
Jian-Kang Cao ◽  
Jun-Jie Ren ◽  
Lin Hong ◽  
Ru-Jin Liang ◽  
...  
Keyword(s):  
High Efficiency ◽  
Nitrogen Sources ◽  
Nitrile Oxides ◽  
Tert Butyl

A high-efficiency strategy for the synthesis of furoxans and 1,2,4-oxadiazoles has been developed, utilizing tert-butyl nitrite (TBN) as nitrogen sources. Azaarene nitrile oxides as activated intermediates were generated in-situ via...

Iron-catalyzed direct amination of azoles using formamides or amines as nitrogen sources in air

2011 ◽  
Vol 47 (12) ◽  
pp. 3652 ◽  
Author(s):  
Jian Wang ◽  
Ji-Ting Hou ◽  
Jun Wen ◽  
Ji Zhang ◽  
Xiao-Qi Yu
Keyword(s):  
Nitrogen Sources ◽  
Direct Amination

scholarly journals Impacts of Initial Sugar, Nitrogen and Calcium Carbonate on Butanol Fermentation from Sugarcane Molasses by Clostridium beijerinckii

Energies ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 694 ◽  
Author(s):  
Patthranit Narueworanon ◽  
Lakkana Laopaiboon ◽  
Niphaphat Phukoetphim ◽  
Pattana Laopaiboon
Keyword(s):  
Calcium Carbonate ◽  
Low Cost ◽  
Nitrogen Sources ◽  
Clostridium Beijerinckii ◽  
Sugarcane Molasses ◽  
Butanol Production ◽  
Gas Stripping ◽  
Box Behnken Design ◽  
Butanol Fermentation

Low-cost nitrogen sources, i.e., dried spent yeast (DSY), rice bran (RB), soybean meal (SM), urea and ammonium sulfate were used for batch butanol fermentation from sugarcane molasses by Clostridium beijerinckii TISTR 1461 under anaerobic conditions. Among these five low-cost nitrogen sources, DSY at 1.53 g/L (nitrogen content equal to that of 1 g/L of yeast extract) was found to be the most suitable. At an initial sugar level of 60 g/L, the maximum butanol concentration (PB), productivity (QB) and yield (YB/S) were 11.19 g/L, 0.23 g/L·h and 0.31 g/g, respectively. To improve the butanol production, the concentrations of initial sugar, DSY and calcium carbonate were varied using response surface methodology (RSM) based on Box–Behnken design. It was found that the optimal conditions for high butanol production were initial sugar, 50 g/L; DSY, 6 g/L and calcium carbonate, 6.6 g/L. Under these conditions, the highest experimental PB, QB and YB/S values were 11.38 g/L, 0.32 g/L·h and 0.40 g/g, respectively with 50% sugar consumption (SC). The PB with neither DSY nor CaCO3 was only 8.53 g/L. When an in situ gas stripping system was connected to the fermenter to remove butanol produced during the fermentation, the PB was increased to 15.33 g/L, whereas the YB/S (0.39 g/g) was not changed. However, the QB was decreased to 0.21 g/L·h with 75% SC.

A simple fluorescence staining technique for in situ soil microorganisms

1975 ◽  
Vol 21 (5) ◽  
pp. 727-729 ◽  
Author(s):  
C. I. Mayfield
Keyword(s):  
Light Source ◽  
Sulfonic Acid ◽  
Soil Microorganisms ◽  
Staining Technique ◽  
Magnesium Salt ◽  
Fluorescence Staining ◽  
Naphthalene Sulfonic Acid

A simple, rapid, staining technique using the magnesium salt of 1-anilino-8-naphthalene sulfonic acid is described. Treatment of soil with an aqueous, membrane-filtered solution (3.5 mg/ml) of the salt causes the soil microorganisms to fluoresce when examined with light from a mercury arc light source.

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