Thiocyanogen

Ag" (precipitate of AgSCN) and (red colouration). Photographic sulphur sensitizers. With oxidizing agents (MnOj, Br ) give thiocyanogen, (SCN)2, which polymerizes above O C. [Pg.395]

In a similar way the use of the 2-methyl-3-isothiocyanato-4-thiocyanato-hept-3-ene (252) prepared from thiocyanogen and the oxoal-kylene phosphorane (251) yields the 2-anilino-4-propyl-5-isopropyl-thiazole (253) by condensation with aniline (Scheme 128). [Pg.299]

The reaction of thiocyanogen (N=CS—SC=N) with cis cyclooctene proceeds by anti addition... [Pg.278]

A related ring closure is also successful in the thiazole series. Treatment of a /3-amino-a,/3-unsaturated ketone with thiocyanogen gave the intermediate thiocyano compound (323) which underwent ring closure to the 2-iminothiazoline derivative (324) (83MI40300). Related reactions are described in Chapter 4.19, and for those involving potassium selenocyanate see Chapter 4.20. [Pg.140]

Thiocyanogen [(SCN)2, 5°, 4 h, 40% yjeld] selectively oxidizes an 5-tri-phenylmethyl thioether to the disulfide (RSSR) in the presence of an 5-di-phenylmethyl thioether. ... [Pg.287]

The monothioacetal is also stable to 12 N hydrochloric acid in acetone (used to remove an TV-triphenylmethyl group) and to hydrazine hydrate in refluxing ethanol (used to cleave an A -phthaloyl group). It is cleaved by boron trifluoride etherate in acetic acid, silver nitrate in ethanol, and tiifluoroacetic acid. The monothioacetal is oxidized to a disulfide by thiocyanogen, (SCN)2- ... [Pg.290]

An S-2-tetrahydropyranyl monothioacetal is oxidized to a disulfide by iodine or thiocyanogen, (SCN)2- ... [Pg.291]

Thiazolidines have been prepared from /3-aminothiols—for example, cysteine—to protect the —SH and — NH groups during syntheses of peptides, including glu-tathione. Thiazolidines are oxidized to symmetrical disulfides with iodine they do not react with thiocyanogen in a neutral solution. [Pg.292]

This activation of the ortho position is most strikingly illustrated in the reactivity of 2,5-dimethylthiophene, which competitive experiments have shown to undergo the SnCb-catalyzed Friedel-Crafts reaction more rapidly than thiophene and even 2-methylthiophene. The influence of the reagent on the isomer distribution is evident from the fact that 2-methoxythiophene is formylated and bromi-nated (with A -bromosuccinimide) only in the 5-position. Similarly, although 3-bromo-2-methylthiophene has been detected in the bromi-nation of 2-methylthiophene with bromine, only the 5-isomer (besides some side-chain bromination) is obtained in the bromination of alkylthiophenes with A -bromosuccinimide. ° However, the mechanism of the latter type of bromination is not established. No lines attributable to 2-methyl-3-thiocyanothiophene or 2-methyl-3-chIoro-thiophene could be detected in the NMR spectra of the substitution products (5-isomers) obtained upon thiocyanation with thiocyanogen or chlorination with sulfuryl chloride. 2-Methyl- and 2-ethyl-thiophene give, somewhat unexpectedly, upon alkylation with t-butyl chloride in the presence of Feds, only 5-t-butyl monosubstituted and... [Pg.48]

Rhodan-. thiocyanogen, thiocyanate of, thiocy-ano-. -aluminium, n. aluminum thiocyanate, -ammonium, n. ammonium thiocyanate, -ammonlbsung, /. ammonium thiocyanate solution,... [Pg.365]

Rhodan-ion, n. thiocyanogen ion, CNS -kali, -kalium, n, potassium thiocyanate, -kalzium, n. calcium thiocyanate, -kupfer, n. cupric thiocyanate, copper(II) thiocyanate. -iSsung, /. thiocyanate solution, -metall, n. (metallic) thiocyanate, -methyl, n. methyl thiocyanate, -natrium, n, sodium thiocyanate, -nickel, m. nickel thiocyanate, -quecksilber, n. mercury thiocyanate, -salz, n. thiocyanate, -sdure, /. (Org. Chem.) thiocyan(at)o acid, -tonerde, /. aluminum thiocyanate. [Pg.365]

Rhodan-verbindtmg, /. thiocyanogen compound. -wasserstoff, m. hydrogen thiocyanate, thiocyanic acid, -wasserstoffskure, /. thiocyanic acid, (formerly) sulfocyanic acid, -zlnn, -zinnozyd, n. stannic thiocyanate, tinilV) thiocyanate, -zinnoiydul, n. stannous thiocyanate, tin (II) thiocyanate. [Pg.365]

Thiocyan, n. thiocyanogen. -kalium, n. potas siuiii thiocyanate. [Pg.445]

Entries 7 to 9 involve other reagents that react by similar mechanisms. In the case of thiocyanogen chloride and thiocyanogen, the formal electrophile is [NCS]+. The presumed intermediate is a cyanothiairanium ion. The thiocyanate anion is an... [Pg.305]

Draw two possible structures for thiocyanogen, (SCN)2, and comment on the relative stability of the structures you draw. [Pg.135]

The compound [Q2C=N—BC12]2 is formed on photochemical chlorination of l,3,5-trimethyI-2,4,6-trichloroborazine 3°) or by interaction of trichlorobor-ane with thiocyanogen trichloride. The reaction of the latter compound with tribromoborane leads to [C12C=N—BBr2]2 21). These processes are summarized in Eq. (7). [Pg.42]

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