A New Synthetic Method for N-Mono- and N,N-Disubstituted Selenoamides

N-Mono and N,N-disubstituted selenoamides are synthesized in a one-pot procedure from nitriles, selenium metal and NaBH₄ followed by the amine group exchange of the intermediate primary selenoamide with an amine.     

<Emphasis Type="Italic">N,N,N′,N′</Emphasis>-tetramethylmethanediamine,efficient reagent for thioles aminomethylation

Efficient method was developed for thiols aminomethylation using N,N,N′,N′-tetra-methylmethanediamine in the presence of Sm and Fe salts. Aminosulfides were obtained in high yields and selectivity.     

Formation,Structural Characterization,and Calculated NMR Chemical Shifts of Selenium‐Nitrogen Compounds from SeCl4 and ArNHLi (Ar = supermesityl,mesityl)

Supermesityl selenium diimide [Se{N(C₆H₂^tBu₃‐2, 4, 6)}₂; Se{N(mes*)}₂] can be prepared in a good yield from the reaction of SeCl₄ and (mes*)NHLi. The molecule adopts an unprecedented anti, anti‐conformation, as deduced by DFT calculations at PBE0/TZVP level of theory and supported by ⁷⁷Se NMR spectroscopy and a crystal structure determination. An analogous reaction involving (C₆H₂Me₃‐2, 4, 6)NHLi [(mes)NHLi] unexpectedly lead to the reduction of selenium and afforded the selenium diamide Se{NH(mes)}₂ that was characterized by X‐ray crystallography and ⁷⁷Se NMR spectroscopy. The Se‐N bonds of 1.847(3) and 1.852(3) Å show normal single bond lengths. The <NSeN bond angle of 109.9(1)° also indicates a tetrahedral AX₂E₂ bonding arrangement around selenium. Two N‐H···N hydrogen bonds link the Se{NH(mes)}₂ molecule with two discrete (mes)NH₂ molecules. In the solid state selenium diamide adopts the anti‐conformation, whereas in solution the presence of both syn‐ and anti‐isomers could be observed. PBE0/TZVP calculations of the shielding tensors of 28 different types of selenium‐containing molecules, for which the ⁷⁷Se chemical shifts are unambiguously known, were carried out to assist the spectral assignment of Se{N(mes*)}₂ and Se{NH(mes)}₂.     

N,N,N′,N′‐Tetraalkylaminoazoxybenzene Derivatives; Convenient Synthesis and Mechanistic Study

N,N,N′,N′‐tetraalkyaminoazoxybenzene derivatives were conveniently prepared by the coupling of N,N‐dialkylnitrosoaniline in the presence of acetone and KOH. The reaction mechanism was proposed and investigated, and the structure of compound 3b was also confirmed by single crystal X‐ray diffractometry.     

Synthesis of Five-Membered N,N,N- and N,N,N,N-Heterocyclic Compounds: Applications of Microwaves

The development of new strategies for the synthesis of small-sized heterocycles has remained a highly attractive but challenging proposition. An overview of the application of microwave irradiation to the synthesis of five-membered heterocyclic compounds containing three and four nitrogen atoms is presented, focusing on the developments in the past 5–10 years. This contribution covers the literature concerning the total synthesis of N,N,N- and N,N,N,N-heterocycles. The literature data are summarized based on the size and type of cycles.     

Zinkkomplexe eines neuen N,N, O‐Liganden

Zinc Complexes of a New N, N, O Ligand The tridentate ligand N, N(2‐dimethylaminoethyl)‐3, 5‐di‐tert.‐butyl‐salicylaldimine ( L H) results from the corresponding salicylic aldehyde and N, N‐dimethyl ethylenediamine. With zinc salts it forms the mononuclear halide complexes [ L ZnCl ˙ CH₃OH] ( 1 ) and [ L ZnI ˙ CH₃OH] ( 2 ) and the presumably polymeric acetate [ L ZnOCOCH₃] ( 3 ). With diethyl zinc and diphenylphosphoric acid it yields the phosphate complex [ L Zn‐OPO(OPh)₂ ˙ CH₃OH] ( 4 ). The coordination of the complexes, which is between trigonal bipyramidal and square pyramidal, and the character of the five donors in the phosphate complex represent the transition state of a hydrolytic substrate cleavage in a zinc enzyme.     

Reversible addition–fragmentation chain‐transfer polymerization of vinyl monomers with N,N‐dimethyldiselenocarbamates

A new range of selenium‐based reversible addition‐fragmentation chain‐transfer (RAFT) agents is described and tested in the polymerization of styrene, acrylates, vinyl esters, and N‐vinylcaprolactam. The synthesized N,N‐dimethyldiselenocarbamates were poor control agents for styrene polymerization, whereas polyacrylates of controlled molar masses and bearing a diselenocarbamate terminal group could be synthesized. The polymerization of vinyl acetate and vinyl pivalate proceeded in a controlled manner as confirmed by size‐exclusion chromatography, matrix‐assisted laser desorption ionization‐time‐of‐flight mass spectrometry, and ⁷⁷Se NMR analyses. The capability of these RAFT agents to control the polymerization of both more‐activated monomers and less‐activated monomers was exemplified through the synthesis of a poly(t‐butyl acrylate)‐b‐poly(vinyl acetate) diblock copolymer. Considering the very broad range of carbamate groups which can be envisioned, this finding opens numerous perspectives for diselenocarbamate‐mediated RAFT polymerization with its specificities yet to be explored. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4361–4368     

Die Kristallstruktur von Tris(N,N-diethyl-N′-benzoylselenoureato)cobalt(III)

The Crystal Structure of Tris(N,N-diethyl-N′-benzoylselenoureato)cobalt(III) Co(C₁₂H₁₅N₂OSe)₃ crystallizes in the trigonal space group P3 . The cell parameters are a = 16.697(4), c = 8.557(8) Å, Z = 2. The structure was solved with Patterson and direct methods and was refined to a final R-value of 4.59%. Co^III is bidentally coordinated to three N,N-diethyl-N′-benzoylselenourea molecules to form a distorted octahedron with facial arrangement of the selenium and oxygen donor atoms. The Co? Se and Co? O bond lengths are 2.328(2) and 1.943(6) Å, respectively. The arrangement of the molecules within the unit cell leads to the formation of hexagonal channels parallel to the crystallographic c-axis. The wall of the channels is formed by carbon atoms of the phenyl group. The diameter of the channels is 8.148 Å.     

Purification of fat-containing wastewater with a complex based on poly-<Emphasis Type="Italic">N,N,N,N</Emphasis>-trimethyl[methacryloyloxyethyl]ammonium methyl sulfate and sodium dodecyl sulfate

Possibility of using complexes based on poly-N,N,N,N-trimethyl[methacryloyloxyethyl]ammonium methyl sulfate and sodium dodecyl sulfate for purification of fat-containing wastewater was examined.     

Heterocycles. CLXIX. Barriers to rotation in some N,N-Dimethyl-N′-heteroaryl,N,N-Diethyl-N′-heteroaryl-substituted formamidines and N,N-Dimethyl-N′-heteroaryl-substituted acetamidines

The free energies of the rotational barriers, ΔG*, about ?CH? NMe₂ bond in N′-heteroaryl N,N-dimethylformamidines (A), about ?CH? NEt₂ bond in N-heteroaryl N,N-diethylformamidines (B), and about ?C(Me)? NMe₂ bond in N′-heteroaryl N,N-dimethylacetamidines (C) have been found to be in the range 17.5–20.1 kcal/mole for type A, 18.8–21.6 kcal/mole for type B and 13–14 kcal/mole or below for type C of compounds, respectively. The compounds of the types A and B exist in the forms IIa, IIIa, IV, V, and VI, while the compounds of the type C exist in the forms IIb and IIIb.     

Silylhydrazine und dimere N,N′‐Dilithium‐N,N′‐bis(silyl)hydrazide – Synthesen,Reaktionen, Isomerisierungen

Silylhydrazines and Dimeric N,N′‐Dilithium‐N,N′‐bis(silyl)hydrazides – Syntheses, Reactions, Isomerisations Di‐tert.‐butylchlorosilane reacts with dilithiated hydrazine in a molar ratio to give the N,N′‐bis(silyl)hydrazine, [(Me₃C)₂SiHNH]₂, ( 5 ). Isomeric tris(silyl)hydrazines, N‐difluorophenylsilyl‐N′,N′‐bis(dimethylphenylsilyl)hydrazine ( 7 ) and N‐difluorophenylsilyl‐N,N′‐bis(dimethylphenylsilyl)hydrazine ( 8 ) are formed in the reaction of N‐lithium‐N′‐N′‐bis(dimethylphenylsilyl)hydrazide and F₃SiPh. Isomeric bis(silyl)hydrazines, (Me₃C)₂SiFNHNHSiMe₂Ph ( 9 ) and (Me₃C)₂‐ SiF(PhMe₂Si)N–NH₂ ( 10 ) are the result of the reaction of di‐tert.‐butylfluorosilylhydrazine and ClSiMe₂Ph in the presence of Et₃N. Quantum chemical calculations for model compounds demonstrate the dyotropic course of the rearrangement. The monolithium derivative of 5 forms a N‐lithium‐N′,N′‐bis(silyl)hydrazide ( 11 ). The dilithium salts of 5 ( 13 ) and of the bis(tert.‐butyldiphenylsilyl)hydrazine ( 12 ) crystallize as dimers with formation of a central Li₄N₄ unit. The formation of 12 from 11 occurs via a N′ → N‐silyl group migration. Results of crystal structure analyses are reported.     

Synthesis and Structure of N,N‐Dinitroamidoborane Complexes

A general approach to the synthesis of borohydride complexes containing one or two dinitroamide fragments has been suggested. Based on a smooth substitution of halide in haloborane or dibromoborane complexes with N ,N ‐dinitroamide salts, this method provides various N ,N ‐dinitroamidoboranes complexes in good yields and in analytically pure form. By means of spectroscopic and computational methods, it was demonstrated that dinitroamidoborane complexes could form as both B,N‐ and B,O‐isomers, which did not interconvert at ambient temperature.     

Unusual Conformational Behavior of 3,7-Dihetera(N,N-;N,O-;N,S-) Bicyclo[3.3.1]Nonan-9-Ols Via Nmr Analysis

Abstract

Based upon the analysis of ¹H NMR data, along with molecular modeling, it was shown that the reduction of 3,7-dihetera(N,N-; N,O-; N,S-)bicyclo[3.3.1]nonan-9-ones by LiAlH₄ led to a mixture of two stereoisomeric secondary alcohols with different orientations of the hydroxyl groups in one of the ring systems. Diaza derivatives in deuterochloroform exist in predominant chair-boat conformations. However, the replacement of nitrogen in one of the heterocycles by oxygen or sulfur led to stereoisomers one of which existed in chair-boat conformation and another in a chair–chair conformation. In all cases the boat conformation is stabilized by formation of an intramolecular hydrogen bond (IMHB) between a lone electron pair of the nitrogen atom and a proton on the pseudo axial hydroxyl group of the other ring.     

N,N, N′,N′-Tetrabutyl-3,6-dioxaoctan-dithioamid,ein ionophor mit Cd2+-Selektivität,Röntgenstrukturanalyse des Cd2+-Komplexes

N, N, N′,N′-Tetrabutyl-3,6-dioxaoctan-dithioamid, an Ionophore with Cd²⁺-Selectivity The CdCl₂-complex of N, N, N′, N′-tetrabutyl-3, 6-dioxaoctanedithioamide crystallizes with the composition [Ligand. Cd₂Cl₄] in space group P1 , a= 14.140, b= 10.025, c= 12.173 Å, α = 95.59°. β = 102.06°. γ = 85.50° Z= 2. Each ligand coordinates two Cd₂₊-ions. Adjacent cations are bridged by two Cl⁺-ions such that infinite bands along the b-axis are formed.     

Synthesis and biological study of a new series of bifunctional organoiron thio‐ and seleno‐terephthalate derivatives (C5H5)Fe(CO)2ECO(C6H4)COX (E = S,X = R2N,RNH, NH2, OH,Cl; E = Se,X = RNH,RS, RCOO,NH2, OH,Cl)

A new series of bifunctional organoiron thio‐ and seleno‐terephthalate complexes — (η‐C₅H₅)Fe(CO)₂ECO(C₆H₄)COX [E = S; X = C₆H₁₁NH, (C₂H₅)₂N; and E = Se; X = P? CH₃? C₆H₄? NH, C₆H₅? C₂N₂O? S, m? NO₂? C₆H₄? CH?CH? COO] — has been synthesized via the organic transformation reactions of the terephthaloyl chloride precursors η‐(C₅H₅)Fe(CO)₂ECO(C₆H₄)COCl with the desired nucleophiles. These new complexes were characterized by elemental analysis, IR and ¹H NMR spectra. The above complexes, in addition to some other selected analogues, were tested for their antifungal, antibacterial and mutagenic activity. Our results show that all the selenium‐containing compounds have antifungal activity on Candida albicans and antibacterial effects against Bacillus subtilis and Staphylococcus aureus. Four of the six selenium‐containing derivatives exhibited growth inhibitory effects against Pseudomonas aeruginosa and/or Escherichia coli. Sulfur‐containing derivatives elicited activity against C. albicans, and each one of them showed activity against at least one of the bacterial strains that have been used in this investigation. Two selenium‐ and two sulfur‐containing derivatives showed mutagenic activity against one or more than one strain of the Salmonella typhimurium using the Ames test. Copyright © 2001 John Wiley & Sons, Ltd.     

New,strong cationic hydrogels: Preparation of N,N,N′,N′‐tetraallyl piperazinium dibromide and its copolymers with N,N‐diallyl morpholinium bromide

N,N,N′,N′‐tetraallyl piperazinium dibromide (TAP) has been prepared in high yields by quaternization of N,N′‐diallyl piperazine with allyl bromide. Herein, we have described preparation of nonhydrolysable, strong, cationic hydrogels by copolymerization of TAP with N,N‐diallyl morpholinium bromide (DAM) in the presence of t‐butyl hydroperoxide as initiator in aqueous solutions. Because the monomer and crosslinker involved consist of quaternary amine functions, these hydrogels are fully cationic and do not carry hydrolysable groups. Contrary to expectations, the quaternary amine hydrogels presented do not show any super absorbency, instead dry gel particles in water undergo spontaneous disintegration with an audible bursting of the particles due to instantaneous, high osmotic pressure. Whereas, in KBr or HBr solutions, the swellings are relatively slow. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1006–1013, 2000     

<Emphasis Type="Italic">peri</Emphasis>-Naphthylenediamines: XXXIX. Synthesis and Structure of <Emphasis Type="Italic">N,N′,N′</Emphasis>-Trimethyl-<Emphasis Type="Italic">N</Emphasis>-nitrosonaphthalene-1,8-diamine Derivatives

The corresponding N-nitroso derivatives were synthesized by the action of nitrous acid on N,N,N′-trimethylnaphthalene-1,8-diamine, N,N,N′-trimethyl-5-nitronaphthalene-1,8-diamine, and N,N,N′-trimethylacenaphthene-5,6-diamine, and molecular structure of the products was studied.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1020–1027.Original Russian Text Copyright © 2005 by Koroleva, Dyablo, Pozharskii, Sennikova, Starikova.     

Mild and Efficient Deprotection of 1,3‐Dithianes with N,N′‐ Diiodo‐N,N′‐1,2‐Ethanediyl‐Bis(p‐Toluenesulphonamide)

Aliphatic and aromatic 1,3‐dithiane are oxidized to the corresponding carbonyl compounds in good yields under mild conditions by N,N′‐diiodo‐N,N′‐1,2‐ethanediyl‐bis(p‐toluenesulphonamide) [NIBTS] and silver nitrate.     

N,N,N′,N′-Tetrabutyl-3,6-dioxaoctan-dithioamid,Ionophor mit Selektivität für Cd2+

N,N,N′,N′-Tetrabutyl-3,6-dioxaoctane-dithioamide, an Ionophore with Selectivity for Cd²⁺ The dioxa-dithioamide 3 behaves as a highly selective ionophore for Cd²⁺ in solvent polymeric membranes. It induces cation-permselectivity in these membranes with a transference number of 1 for Cd(NO₃)₂- and of 2 for CdCl₂-solutions. In the presence of a proton carrier, 3 may be used to selectively pump Cd²⁺ through membranes by coupling with a pH gradient.     

[2,2′‐(1,3,5,8,10,12‐Hexaazacyclotetradecane‐3,10‐diyl)diethanol‐κ4N1,N5,N8,N12]bis(thiocyanato‐κS)copper(II)

In the crystal structure of the title compound, [Cu(NCS)₂(C₁₂H₃₀N₆O₂)], the Cu atom lies on an inversion centre and has an elongated octahedral coordination, with Cu—N distances of 2.004 (2) and 2.015 (2) Å, and a Cu—S distance of 2.9696 (10) Å. The 2,2′‐ethanol chains are axially oriented. The mol­ecules are linked to form a three‐dimensional network via O—H?N, N—H?O and N—H?S hydrogen bonds.