A new chiral recognition in aminolysis of 3-acyl-4(r)-methoxycarbonyl-1,3-thiazolidine-2-thione with racemic amines

A chiral recognition was observed in aminolysis of 3-acyl-4(R)-methoxycarbonyl-1,3-thiazolidine-2-thione $\text{1}$ by racemic amine $\text{2}$ to give an optically active amide (S-excess) and amine (R-excess).     

Synthesis of t-butyldimethylsilyl enol ethers from sterically hindered ketones

Ketones react rapidly with $\text{t}$-butyldimethylsilyl triflate and amine bases to form $\text{t}$-butyldimethylsilyl enol ethers in high yields.     

Stereochemistry of nucleophilic attack by amine on a cationic π-allylnickel complex

Reaction of the π-allylnickel complex $\text{3}$ with morpholine gave a 1:1 mixture of the amines $\text{4}$ and $\text{5}$ indicating that the amine has attacked the π-allyl moiety from the side trans to nickel.     

New facile synthesis of N-sulfinylamine derivatives using N,N′-sulfinylbisimidazole and N-(chlorosulfinyl)imidazole

Treatment of amine derivatives such as amines, sulfonamides, and amides with N,N′-sulfinylbisimidazole $\text{1}$ and N-(chlorosulfinyl)imidazole $\text{2}$$\text{in situ}$ respectively gives the corresponding N-sulfinylamine derivatives ($\text{3}$); the latter reaction using N-(chlorosulfinyl)imidazole $\text{2}$ yields $\text{3}$ in almost quantitative yields at 20°C under mild conditions.     

Perfluoroalkyl derivatives of nitrogen. Part LI [1]. Reaction of the N-halogenobistrifluoromethylamines (CF3)2NX (X=Cl,Br) with norbornadiene

Reaction of the amines (CF₃)₂NX (X=Cl,Br) with norbornadiene either in solvent (CH₂Cl₂) at ?78 °C in the dark or in the vapour phase at 20 °C in daylight gives a mixture of 3-halogeno-5-($\text{NN}$-bistrifluoromethylamino)nortricyclene ($\text{exo}$, $\text{endo}$-and $\text{exo}$, $\text{exo}$-isomers) and $\text{exo}$-5-($\text{NN}$-bistrifluoromethylamino)- $\text{anti}$-7-halogenonorbornene in quantitative yield formed $\text{via}$ halonium ion addition to the diene. The reaction of the amine (CF₃)₂NBr in solvent Me₂O or Et₂O at ?78 °C in the dark gives the same products in low yield, together with 3-bromo-5-alkoxynortricyclene ($\text{exo}$, $\text{endo}$- and $\text{exo}$, $\text{exo}$-isomers) and the amine (CF₃)₂NR (R=Me, Et) in high yield.     

Reaction of tertiary allylic amines with butadiene catalyzed by palladium

Tertiary allylic amines react with butadiene in the presence of palladium(O) with cleavage of the carbon-nitrogen bond of the allylic amine and formation of the unsaturated tertiary amine $\text{4}$.     

Cis - oxyamination routes to amimo sugars: A simple synthesis of holacosamine

The known D-$\text{threo}$ hex-2-enopyranoside $\text{1a}$ is converted into an N-methyl allyl amine, the methyl urethane of which undergoes electrophile-induced cyclisation to give the iodocyclic urethane $\text{9}$. The $\text{cis}$ relationship of H3 and H4 in the latter is confirmed by NMR spectroscopy. Reduction at C2 and C6 is done simultaneously and the cyclic urethane is hydrolysed. The amino group is then acetylated and the hydroxy group methylated.     

Chiral and stereoselective total synthesis of (−)-deoxoprosopinine and (−)-deoxoprosophylline

(?)-Deoxoprosopinine and (?)-deoxoprosophylline were synthesized starting from $\text{L}$-serine by a route involving the intramolecular aminomercuration of a chiral ?,ζ-unsaturated amine.     

Preparation of undecacarbonyltriosmium derivatives

Undecacarbonyltriosmium derivatives have been prepared by treatment of dodecacarbonyltriosmium with amine oxide in low ratio $\text{(1}\text{1)}$. Substitution reactions with halogen acids lead to HOs(CO)₁₁X derivatives which readily lose carbon monoxide to yield HOs₃(CO)₁₀X compounds.     

Synthesis of (±)-3-dexosy-16-azaequilenin

Condensation of methacrylyl chloride with the amine obtained on lithium aluminium hydride reduction of 1,2-naphthocyclobuten-3-carboxamide gave a propenamide which on refluxing in $\text{O}$-dichlorobenzene cyclised to (±)-3-dexoy-16-azaequilenin.     

Tris(2-deoxy-2-l-ascorbyl)amine: a novel compound related to a fairly stable free radical

Tri(2-deoxy-2-L-ascorbyl)amine ($\text{1}$), isolated as one of the new products of reaction of dehydroascorbic acid with an α-amino acid, produces by air oxidation a blue free radical species which is fairly stable in water.     

Nachbargruppeneffekte bei der aminolyse von estern—I: Kinetik der aminolyse von nitrophenylacetaten mit n-butylamin in dioxan

The kinetics of the aminolysis of different nitrophenylacetates were investigated with n-butylamine in dioxane at 20°C. The reaction rate can be described up to high concentrations of amine (~1 mole dm^?3) by the equation v=k₂[ester][amine]+k₃[ester][amine]². The ratio $\text{k}{}_3\text{k}{}_2$ is larger for p-nitrophenylacetates than for o-nitrophenylacetates, while for 2,4-dinitrophenylacetates a third order term is not observed.     

Applications of new peptide protective groups 1-- a synthesis of bis-s-acetamidomethyl dihydrosomatostatin

A synthesis of $\text{bis}$-S-Acetamidomethyl dihydrosomatostatin is reported in which the C-terminal carboxyl function is protected by the Maq ester function and the N-terminal amine as well as two ε-amino groups of lysine residues are protected as Tcroc urethanes. Clean removal of these groups is reported.     

Semimicro determination of hydroxy and amino compounds using pyromellitic dianhydride

The PMDA method for determining hydroxyl and primary and secondary amino groups was applied on the semimicro scale. A sample containing 0.4 to 0.6 mEq of amine or hydroxyl was reacted with 25 ml of 0.04 M PMDA in a routine analysis. The unconsumed PMDA was titrated with 0.08 N base. For colorless clear samples, the phenolphthalein endpoint was used; for colored or turbid samples, a potentiometric titration is recommended. Further scaling down of the method may be feasible by increasing the $\text{PMDA}\text{OH}$ ratio.     

Ueber trishydrofluoride tertiaerer amine und ihren einsatz als fluorierungsmittel

Tertiary amine trishydrofluorides are stable complexes which are distillable $\text{in vacuo.}$ They can be handled without hazard and do not corrode borosilicate glass. They are convenient agents therefore, in nucleophilic replacement reactions of chlorine or bromine atoms by fluorine forming homogeneous reaction mixtures often leading to higher yield under very mild conditions. Examples are given for the preparation of fluoroacetone, cyanuric fluoride, difluorophosgene, oxalyl fluoride and sulfur tetrafluoride.     

Models of folate coenzymes 13 : Syntheses of benzo[a]quinolizine and indolo[2,3-a]quinolizine derivatives via carbon fragment transfer from folate coenzyme models

Anions of β,β-disubstituted acetyl acetates ($\text{2}$, CH₂COCR₁R₂COOR₃; R₁= R₂ = Me₂ R₁ = Et, R₂ = COOMe, R₁ = Et, R₂ = SPh) add to 1-tosyl-3,4,4-trimethyl-Δ -imidazolinium iodide ($\text{3}$) to give the corresponding imidazolines ($\text{4}$), which are regarded as models of methylenetetrahydrofolate These models transfer C(2) of the imidazalodine -with its appended carbon fragment- to tryptamine and 2-(3,4-dimethoxybenzene)ethyl amine to yield enaminoketo ester intermediates which can be converted into benzo[a]quinolizine and indolo[2,3-a]quinolizine derivatives, respectively, in two cyclization steps. The intermediate derived from transfer of carbon fragment CH-CH₂COC(SPh) (Et) COOMe to tryptamine exhibits reactions which involve nucleophilic displacement at a sulfur atom of a thio ether bond.     

Structure de la gouregine,alcaloïde orginal apparente aux cularines

The structure of guoregine, a new isoquinoline alkaloid from $\text{G}$$\text{u}$$\text{a}$$\text{t}$$\text{t}$$\text{e}$$\text{r}$$\text{i}$$\text{a}$$\text{o}$$\text{u}$$\text{r}$$\text{e}$$\text{g}$$\text{o}$$\text{u}$, Annonaceae, has been deduced by spectral analysis and confirmed by an X-ray structure determination. It is the first member of a new class of cularine-related alkaloids (α-$\text{g}$$\text{e}$$\text{m}$-dimetyltetradehydrocularines).     

The resolution of racemic 2-alkyl-1-aminocyclopropane-1-carboxylic acids

Practical procedures for the resolution of racemic modification of (1$\text{R}$, 2$\text{S}$)-and (1$\text{S}$, 2$\text{R}$)-1-amino-2-ethylcyclopropane-1-carboxylic acid $\text{1a}$,$\text{b}$,(1$\text{R}$, 2$\text{S}$)- and (1$\text{S}$, 2$\text{R}$)-1-amino-2-methylcyclopropane-1-carboxylic acid $\text{2a}$,$\text{b}$, and (1$\text{R}$, 2$\text{R}$)- and (1$\text{S}$, 2$\text{S}$)-1-amino-2-methylcyclopropane-1-carboxylic acid $\text{3a}$,$\text{b}$ are described; the structures as $\text{1a}$,$\text{2a}$, and $\text{3a}$ were confirmed by X-ray-crystallographic methods.