N-alkylated Products Research Articles

ChemInform Abstract: THE REACTION OF ALKYL HALIDES WITH MERCURIC THIOCYANATE

AbstractDie Titelreaktion z.B. der Bromide (II) ergibt in wenig polaren Lösungsmitteln wie n‐Hexan und 1,2‐Dichlor‐äthan die Isothiocyanate (I) als Hauptprodukte, während mit K‐thiocyanat in DMF vorwiegend die Thiocyanate (III) erhalten werden.

Nucleophilic Reactions of Imines

The reaction of imines with various electrophiles have afforded only N-alkylated products, contrary to earlier reports.

The chemistry of 2,1-benzisothiazoles. VIII. Tautomerism of 2,1-Benzisothiazolin-3-one and the preparation of N- and O-alkylated derivatives

Both N-alkyl and O-alkyl derivatives of 2,1-benzisothiazolin-3-one (1) have been prepared by unambiguous syntheses. Comparison of ultraviolet spectra indicates that (1) exists in the keto form rather than as its tautomer 2,1-benzisothiazol-3-ol (2). Alkylation of the anion of (1) yields N-alkylated products.

The Reaction of Alkyl Halides with Mercuric Thiocyanate

Abstract The reaction of secondary and tertiary alkyl halides with mercuric thiocyanate in less-polar solvents e.g., n-hexane, di-n-butyl ether, and 1,2-dichloroethane) was found to afford predominantly N-alkylation products, alkyl isothiocyanates, in contrast to the reaction with potassium salt in DMF. Especially, from t-butyl bromide, α-phenethyl bromide and benzhydryl chloride, the corresponding pure isothiocyanates were obtained in good yields. A most probable reaction mechanism is suggested, based on the relative rate data, the stereochemical result of the reaction with optically active α-phenethyl bromide, and the well-known catalytic effect of silver or mercury salt in SN1 reaction.

Reaction of N-(4-oxo-2-methyl-2-pentyl) -?-phenylnitrone with hydroxylamine

1. The reaction of mesityl oxide with anti-benzaldoxime gives the N-alkylation product, namely N-(4-oxo-2-methyl-2-pentyl)-α-phenylnitrone; the reaction is reversible. 2. The treatment of N-(4-oxo-2-methyl-2-pentyl)-α-phenyl-nitrone with hydroxylamine gives N-(4-hydroxyimino-2-methyl-2-pentyl)hydroxylamine and 5-hydroxy-3,3,5-trimethylisoxazolidine. The latter is the intermolecular cyclization product of the intermediate β-hydroxylamine ketone.

Alkylation of 3-isoxazolidone

The alkylation of 3-isoxazolidone and its metal salts with diazomethane and alkyl halides was investigated for the first time. The alkylation products are a mixture of two isomers — derivatives of the lactam and lactim forms of 3-isoxazolidone. The major component in all cases is the N-alkylation product. The percentage of isomeric imino ethers depends on the nature and structure of the reagents.

Formation of enamines by alkylation of imines

cf. CA 64, 12473c. With ice-cooling, 1 equiv. alkylating agent was added to one equiv. of the imine in 1M soln. in a solvent in the presence of NaH to give both N- and C-alkylated products. The following summarizes the date (imine, solvent, alkylating agent, % unreacted imine, % N-alkylated product, % C-alkylated product, % polyalkyl product): PhMeC:NH (I), (EtOCH2)2 (II), Et3OBF4 (III), 8, 88, 4, -; I, II, Et2SO4, 9, 49, 42, -; I, II, EtI (IV), 5, 5, 90, -. In the following, NaNH2 replaced NaH (same data given): cyclohexanon imine (V), hexamethylphosphoric triamide (VI), III, 29, 53, 18, -; V, VI, Me2SO4 (VIa), 11, 75, 10, 4; V, VI, IV, 15, 17, 56, 12; Et2C:NH (VII), VI, III, 26, 29, 42, 3; VII, VI, VIa, 17, 57, 26, 0; and VII, VI, IV, 20, 0, 71, 9. [on SciFinder (R)]

Studies on the Azaindolizine Compounds. XIII. Alkylation of 5-Methyl-s-triazolo [1, 5-a] pyrimidin-7-ol.

The alkylation of 5-methyl-s-triazolo [1, 5-a] pyrimidin-7-ol (I) with alkyl iodide and dialkyl sulfate always afforded the two N-alkylated products (IIa-b and IIIa-b). The structure of these products was established to be 4-alkayl-5-methyl-s-triazolo [1, 5-a]-pyrimidin-7 (4H)-ones and 3-alkyl-5-methyl-s-triazolo [1, 5-a] pyrimidin-7 (3H)-ones respectively.

Thiol Esters and Ethers of Cysteine

Thiol esters of L-cysteine have been prepared from either N-carbobenzyloxy-L-cysteine or N-formyl-L-cysteine by using two-phase reaction mixtures. The carbobenzyloxy groups were removed by nonhydrolytic cleavage with hydrogen bromide. Thio ethers of L-cysteine base were obtained by alkylation in a two-phase reaction and were obtained uncontaminated with N-alkyl products. One compound, the car-boxymethyl thio ether, showed slight antiviral activity.