Radical generation from electroreduction of aryl and benzyl ammonium salts: synthesis of organoboronates

2021 ◽  
Author(s):  
Xianqiang Kong ◽  
Long Lin ◽  
Qianjin Chen ◽  
Bo Xu
Keyword(s):  
Room Temperature ◽  
Ammonium Salts ◽  
Benzyl Ammonium ◽  
Radical Generation

We report a direct electrocatalytic borylation of aryl and benzyl trimethylammonium salts with bis(pinacolato)diboron at room temperature.

Green Amide Bond Formation in Water via Direct Coupling of Metal Carboxylate Salts with Ammonium Salts at Room Temperature

2021 ◽  
Author(s):  
Truong Thanh Tung ◽  
John Nielsen
Keyword(s):  
Room Temperature ◽  
Bond Formation ◽  
Direct Coupling ◽  
Ammonium Salts ◽  
Amide Bond ◽  
Metal Carboxylate ◽  
Amide Bond Formation ◽  
Simple Protocol

Herein, we report the green, expedite, and practically simple protocol for direct coupling of carboxylate salts and ammonium salts under ACN/H2O conditions at room temperature without the addition of tertiary...

scholarly journals The Isomorphous Structures of Ammonium trans-Diiodobis(ethanedial-dioximato-(1–)-N,N′)cobaltate(III) and Ammonium trans-Diiodobis(ethanedial-dioximato-(1–)-N,N′)rhodate(III): Extended Metaloximate Chains with a Novel ···I–M–I···I–M–I··· Zigzagged Structure

1990 ◽  
Vol 45 (11) ◽  
pp. 1508-1512 ◽  
Author(s):  
Michel Mégnamisi-Bélombé ◽  
Bernhard Nuber
Keyword(s):  
Room Temperature ◽  
Ammonium Salts ◽  
Monoclinic Space Group ◽  
Hydroxyl Groups ◽  
Coordination Geometry ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Anionic Complexes ◽  
Complex Anions

The ammonium salts of the complex anions trans-diiodobis(ethanedial-dioximato)-cobaltate(III), [Col2(GH)2]-, and trans-diiodobis(ethanedial-dioximato)rhodate(III), [RhI2(GH)2]- (GH- = ethanedial dioximate or glyoximate), have been synthesized and their structures determined from single crystal X-ray diffraction data at room temperature. The crystals of the two salts are monoclinic, space group C2/c. NH4[CoI2(GH)2] (I) crystallizes as dark-brown prisms with a greenish reflectance; its crystal data are: C4H10Col2N5O4, Mr = 504.90; a = 8.910(6), b = 11.700(9), c = 11.691(6) Å; β = 93.55(5)°; V = 1216.4 Å3; Z = 4; Dc = 2.78 Mg m-3. NH4[RhI2(GH)2] (II) crystallizes as yellow-brown blocks with crystal data: C4H10I2N5O4Rh, Mr = 548.88; a = 9.038(4), b = 11.949(5), c = 11.770(3) Å; β = 95.54(3)°; V = 1265.16 A3; Z = 4; Dc = 2.87 Mg m-3. The two structures were refined to a final RW = 0.045 for 1209 observed independent reflections and 95 parameters for I, and to a final RW = 0.040 for 1922 observed independent reflections and 87 parameters for II. The coordination geometry around Co or Rh in the anionic complexes is a distorted (4 + 2) octahedron of four equatorial chelating N atoms and two apical iodides. The H atoms of the hydroxyl groups are involved, as usual, in intramolecular O—H—O bridges with uniform Ο···Ο separations of 2.582 Å for I, and 2.713 Å for II. The rectilinear I—Co—I or I—Rh—I triads form “infinite” zigzag chains extending parallel to the ab plane, with a weak I—I contact of 3.988 Å for I, and 4.010 Å for II.

Rh-Catalyzed tandem C–C/C–N bond formation of quinoxalines with alkynes leading to heterocyclic ammonium salts

2019 ◽  
Vol 17 (8) ◽  
pp. 2148-2152 ◽  
Author(s):  
Kangkan Talukdar ◽  
Subhasish Roy ◽  
Raghunath Bag ◽  
Tharmalingam Punniyamurthy
Keyword(s):  
Room Temperature ◽  
Photophysical Properties ◽  
Bond Formation ◽  
Ammonium Salts

Rh-Catalyzed oxidative C–H annulation of 2-arylquinoxalines with alkynes is described to furnish a diverse variety of quinoxalinium salts at room temperature. The substrate scope, isolation of the rhodacycle and photophysical properties are the important features.

scholarly journals Photoinduced Copper-Catalyzed Asymmetric C-O Cross-Coupling

2021 ◽  
Author(s):  
Jun Chen ◽  
Yu-Jie Liang ◽  
Peng-Zi Wang ◽  
Guo-Qing Li ◽  
Bin Zhang ◽  
...  
Keyword(s):  
Room Temperature ◽  
Cross Coupling ◽  
Asymmetric Induction ◽  
Light Emitting ◽  
Bond Forming ◽  
Redox Active ◽  
Reaction Proceeds ◽  
Earth Abundant ◽  
Radical Generation ◽  
Allylic Esters

<b>Whereas considerable advances have recently been achieved in radical-involved catalytic asymmetric C-N bond formation, there has been little progress in the corresponding C-O bond-forming processes. Here we describe a photoinduced copper-catalyzed cross-coupling of readily oxime esters and 1,3-dienes to generate diversely substituted allylic esters with high regio- and enantioselectivity (>75 examples; up to 95% ee). The reaction proceeds at room temperature under excitation by purple light-emitting diodes and features the use of a single, earth-abundant copper-based chiral catalyst as both the photoredox catalyst for radical generation and the source of asymmetric induction in C-O coupling. Combined experimental and DFT computational studies suggest the formation of π-allylcopper complex from redox-active oxime esters as bifunctional reagents and 1,3-dienes through a radical-polar crossover process.</b>

Some Characteristics of the Enzymes of the Pyloric Caeca of Cod and Haddock

1937 ◽  
Vol 3 (5) ◽  
pp. 473-485 ◽  
Author(s):  
W. W. Johnston
Keyword(s):  
Protease Activity ◽  
Room Temperature ◽  
Maximum Activity ◽  
Hydrogen Ion ◽  
Ammonium Salts ◽  
Ion Concentrations ◽  
Pyloric Caeca ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of ◽  
Partial Vacuum

Investigation of fish enzymes for leather bates reveals that those of the pyloric caeca show their greatest influence on casein and collagen at hydrogen ion concentrations of approximately pH 8. The protease showed its maximum activity towards casein at a temperature of 45 °C. Ammonium salts at certain concentrations increased the rate of hydrolysis of collagen by about 40 per cent, but had no like stimulating effect on the hydrolysis of casein. A comparison showed that pyloric caeca enzymes were just as satisfactory as commercial leather bates or hog pancreas. When the pyloric caeca are allowed to autolyse at room temperature, the protease activity is constant for the first 24 hours, declines rapidly during the next 80 hours, and slowly thereafter. The most suitable method for preparing a dried preparation was by evaporation under partial vacuum, which, however, is accompanied by some loss of activity.

Structures ofN-acetyl-DL-isoleucine,N-acetyl-DL-alloisoleucine and their ammonium salts; role of ammonium ions in crystal structure formation

2016 ◽  
Vol 72 (4) ◽  
pp. 650-657
Author(s):  
Tatsuo Yajima ◽  
Makiko Kimura ◽  
Yoshihiro Hori ◽  
Tadashi Shiraiwa
Keyword(s):  
Hydrogen Bond ◽  
Room Temperature ◽  
Optically Active ◽  
Ammonium Salts ◽  
Ammonium Ion ◽  
Amino Group ◽  
Ammonium Ions ◽  
Screw Axis ◽  
Crystal Structure Formation

The crystal structures ofN-acetyl-DL-isoleucine,N-acetyl-DL-alloisoleucine and their ammonium salts show that these four compounds exist as racemic compounds around room temperature. The two ammonium salts are arranged around a 21screw axis, forming a helical column which consists of ammonium ions and single enantiomeric anions similar to the crystals of the ammonium salts of optically activeN-acetyl-L-isoleucine andN-acetyl-D-alloisoleucine. The ammonium ion and the carboxylate ion in the helix are connected by three hydrogen bonds, the fourth hydrogen bond being formed between the ammonium ion and an external acetyl amino group of the neighboring helical column. The fourth hydrogen bond is formed between the ammonium ion and an external acetyl amino group of the neighboring 21column. AmmoniumN-acetyl-DL-alloisoleucinate was revealed to exist as an unstable racemic compound due to conformational similarity between the racemic and optically active compounds in the solid state and was optically resolved by fractional crystallization at 293 K.

Nickel-Catalyzed N-Arylation of Cyclopropylamine and Related Ammonium Salts with (Hetero)aryl (Pseudo)halides at Room Temperature

ACS Catalysis ◽  
2017 ◽  
Vol 7 (9) ◽  
pp. 6048-6059 ◽  
Author(s):  
Joseph P. Tassone ◽  
Preston M. MacQueen ◽  
Christopher M. Lavoie ◽  
Michael J. Ferguson ◽  
Robert McDonald ◽  
...  
Keyword(s):  
Room Temperature ◽  
Ammonium Salts ◽  
Pseudo Halides

Transition-metal-free and base promoted C–C bond formation via C–N bond cleavage of organoammonium salts

2021 ◽  
Author(s):  
Tao Zhang ◽  
Kunyu Wang ◽  
Yuting Ke ◽  
Yuanyuan Tang ◽  
Long Liu ◽  
...  
Keyword(s):  
Transition Metal ◽  
Bond Cleavage ◽  
Bond Formation ◽  
Ammonium Salts ◽  
Metal Free ◽  
Bond Forming ◽  
Benzyl Ammonium

A transition-metal-free and base promoted C–C bond forming reaction of benzyl C(sp3)-H bond with organoammonium salts via C–N bond cleavage has been reported. Benzyl ammonium salts as well as cinnamyl...

scholarly journals Structures of relevant ammonium salts in fertilizers

2010 ◽  
Vol 66 (3) ◽  
pp. 358-365 ◽  
Author(s):  
J. M. Montejo-Bernardo ◽  
S. García-Granda ◽  
A. Fernández-González
Keyword(s):  
Room Temperature ◽  
Rietveld Method ◽  
Structural Models ◽  
Ammonium Salts ◽  
Structure Packing ◽  
Double Salts ◽  
Ionic Distribution ◽  
Anions And Cations ◽  
State Ionic ◽  
Similar Crystal Structure

The crystal structures of two double salts of ammonium nitrate (AN) and ammonium sulfate (AS) are reported. The double salts 2NH4NO3·(NH4)2SO4 (2AN·AS) and 3NH4NO3·(NH4)2SO4 (3AN·AS) show a very similar crystal structure packing with alternating layers of anions and cations. The solid-state ionic distribution is controlled by an extensive hydrogen-bonding network with ammonium groups as the donors and O atoms acting as the acceptors. Crystallographic studies were conducted at both room temperature (293 K) and 100 K. Increasing the temperature involves shortening the b axis in the case of the 3AN·AS salt. Quantification of fertilizer mixtures using the Rietveld method was also carried out by means of the structural models reported in this paper for both salts.

Palladium-Catalyzed Coupling of Terminal Alkynes with Benzyl Ammonium Salts

2019 ◽  
Vol 84 (18) ◽  
pp. 12192-12197 ◽  
Author(s):  
Silin Xu ◽  
Zhenming Zhang ◽  
Chunyu Han ◽  
Wenkai Hu ◽  
Tiwen Xiao ◽  
...  
Keyword(s):  
Ammonium Salts ◽  
Terminal Alkynes ◽  
Benzyl Ammonium ◽  
Palladium Catalyzed
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