Tosyl Isocyanate Research Articles

ChemInform Abstract: A Facile Procedure for the Synthesis of N‐(Tosyl)‐2‐iminoacetic Acid Esters, Important Enophiles for the Direct Synthesis of Exotic α‐Amino Acids.

AbstractThe N‐(tosyl)iminoacetates (III) are prepared by aluminum trichloride catalyzed reaction of tosyl isocyanate (I) with the glyoxalates (II).

Alkyl Shifts in 1,4‐Dipoles from Tosyl Iso(thio)cyanate and Imido(thio)carbonates or Isoureas

AbstractO→N alkyl shifts are observed in the dipoles 3, 13 from tosyl isocyanate (2a) and imido(thio)carbonates 1 (12) to give (thio)allophanates 5 (14). Similarly, addition of tosyl isothiocyanate (2b) to isourea 24a leads to the product 28 of an O → S methyl shift. A cross‐over experiment involving 2a and imidothiocarbonates 12b,c gives the four products 14a–d proving the intermolecular nature of the rearrangement. However, on mixing 2a and isoureas 24a,b or 2b and imido(thio)carbonates 1 (12), the reaction stops at the stage of dipoles 8, 19, 25a,b.

Synthesis and Cyclization Reaction of 2-(Hydroxyimino)alkylN,N-Dialkylthiocarbamates,S-[2-(Hydroxyimino)alkyl]O-Methyl Dithiocarbonate, and Alkyl 2-(Hydroxyimino)alkyl Trithiocarbonates

2-(Hydroxyimino)alkyl dialkyldithiocarbamates and alkyl 2-(hydroxyimino)alkyl trithiocarbonates react with tosyl isocyanate as dehydrating agent to give bis(4-isothiazolyl) disulfides in moderate yields. However, treatment of S-[2-(hydroxyimino)phenylethyl] O-methyl dithiocarbonate with tosyl isocyanate affords a novel heterocycle 3-phenyl-4H-1,5,2-oxathiazine-6-thione, in 49% yield.

ChemInform Abstract: Reaction of Aromatic N‐Oxides with Dipolarophiles. Part 11. 1,3‐Dipolar Cycloaddition Reaction of Pyridine N‐Oxides with Tosyl Isocyanate and One‐Pot Synthesis of 2‐Oxooxazolo[4,5‐b]pyridine Derivatives.

AbstractDie Reaktion der Pyridin‐N‐oxide (I) mit p‐Toluolsulfonylisocyanat (II) wird untersucht.

Reaction of aromatic N-oxides with dipolarophiles. XI 1,3-Dipolar cycloaddition reaction of pyridine N-oxides with tosyl isocyanate and one-pot synthesis of 2-oxooxazolo(4,5-b)pyridine derivatives.

The cycloaddition reactivity of tosyl isocyanate toward pyridine N-oxides was calculated by the CNDO/2 method using a perturbation equation, and the results indicated that the initial stage of the reaction might be controlled by the coulombic attraction. The 1, 3-dipolar cycloaddition reaction of tosyl isocyanate with two equivalents of 3, 5-dibromopyridine N-oxide in refluxing benzene gave 6-bromo-2-oxooxazolo[4, 5-b]pyridine, while the use of one equivalent of 3, 5-dichloropyridine N-oxide gave 6, 7a-dichloro-2-oxo-3-tosyl-3a, 7a-dihydrooxazolo[4-, 5-b]pyridine, formed from the 1, 5-sigmatropic rearrangement of the corresponding primary cycloadduct. When the reaction was carried out in the presence of triethylamine in benzene, 6-halogeno-2-oxo-3-tosyloxazolo[4, 5-b]pyridine was isolated.The observed activation parameters, as well as the small solvent effects, may be interpreted in termas of a concerted pathway.The reaction should be very valuable as a one-pot synthesis of 2-oxooxazolo[4, 5-b]pyridines, which are pyridine analogues of 5-chloro-2-benzoxazolinone.

ChemInform Abstract: NOVEL CYCLIZATION OF 2‐(HYDROXYIMINO)‐2‐PHENYLETHYL DITHIOCARBOXYLATES

AbstractBeim Erhitzen mit Tosylisocyanat (II) werden die Oxime (1) zu den Isothiazolen (III) cyclisiert.

NOVEL CYCLIZATION OF 2-(HYDROXYIMINO)-2-PHENYLETHYL DITHIOCARBOXYLATES

Abstract 2-(Hydroxyimino)-2-phenylethyl arenedithiocarboxylates were cyclized to isothiazoles by the treatment with tosyl isocyanate.

Bicyclofulvene—VI : Regioselektive (2 + 2)-cycloadditionen an methylennorbornadien

Ketene imminium ion ( 4), diphenyl ketene, tosyl isocyanate and tetracyanoethylene add selectively to the semicyclic double bond of 1. This is interpreted to result from the polarity of the semicyclic double bond in 1.

ChemInform Abstract: REACTION OF TRIMETHYLSILYL CYANIDE WITH ISOCYANATES

AbstractTrimethylsilylcyanid (I) und die Isocyanate (II) reagieren bei 50°C über die Zwischen= Stufen (III) und (IV) zu den Trimethylsilylimino‐imidazolidindionen (V), die zu den Trionen (VI) bzw. Iminen (VII) gespalten werden.

Reaction of trimethylsilyl cyanide with isocyanates

Trimethylsilyl cyanide reacts with aryl isocyanates to give 5-iminodiazolidinediones (1 : 2 adducts), while tosyl isocyanate afforded the 1 : 1 adduct.

Reaction of tosyl isocyanate with carboxylate salts

Reaction of tosyl isocyanate with carboxylate salts

Synthesis and Pharmacological Evaluation of Some Tosylbiurets and Tosylthiocarbamates as Potential Hypoglycemic Agents

The synthesis and preliminary pharmacological screening of some p-toluenesulfonyl-biurets and alkyl p-toluenesulfonylthiocarbamates are described. The biurets were prepared by refluxing tosyl isocyanate with the appropriate urea, and the thiocar-bamates were formed by the addition of selected mercaptans to the same isocyanate. None of the tosylbiurets possessed hypoglycemic activity; however, propyl tosyl-thiocarbamate lowered serum glucose levels in mice to approximately the same extent as tolbutamide.