Syntheses of 1,2,4-benzothiadiazine 1-oxides and 1,2,4-benzothiadiazines

Finch, Neville; Ricca, S.; Werner, L. H.; Rodebaugh, Ronald K.

doi:10.1021/jo01305a009

Cited by 21 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fortunately, the resulting S-oxides can, in principle, be reduced to 4H-thiadiazines 2 with phosphines. 26 Although our main focus is on liquid crystalline derivatives of 1, we have also briefly considered the suitability of 1 for molecular conductors. Our computational results in Table 6, supported by voltammetric studies, indicate that the redox properties of the radicals are generally favorable in the context of molecular conductors.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Experimental and Theoretical Studies of Fused-Ring Persistent [1,2,4]Thiadiazinyl Radicals

Zienkiewicz

Kaszyński

2004

J. Org. Chem.

View full text Add to dashboard Cite

Five persistent radicals 1a-1e were generated by the oxidation of 4H-[1,2,4]thiadiazines 2a-2e and studied with ESR and UV-vis spectroscopy. Three of the radicals, 1a, 1d, and 1e, were generated in high yields (>90%) using either SO(2)Cl(2)/amine in toluene or AgO/K(2)CO(3) in a toluene/MeCN mixture. Halogenated radicals 1d and 1e were sufficiently stable for chromatographic isolation and vacuum sublimation. The solution stability of the fluorinated 1d was measured at t(1/2) approximately 4 months in the absence of oxygen, and 1e at t(1/2) approximately 40 min in the presence of air. The crystal and molecular structures of 1d were determined by X-ray crystallography showing columns of parallel almost evenly spaced planar heterocycles connected by infinite ...N...S... chains. Cyclic voltammetry of 1d and 1e shows reversible reduction waves at about 0 V and irreversible oxidations at about 1.2 V. Spectral and electrochemical properties of 1 were well reproduced by DFT methods.

show abstract

Section: Discussionmentioning

confidence: 99%

“…The reaction of 1 with oxygen takes place at the sulfur center and gives rise to the S -oxides 4 . Fortunately, the resulting S -oxides can, in principle, be reduced to 4 H -thiadiazines 2 with phosphines …”

Section: Discussionmentioning

confidence: 99%

Experimental and Theoretical Studies of Fused-Ring Persistent [1,2,4]Thiadiazinyl Radicals

Zienkiewicz

Kaszyński

2004

J. Org. Chem.

View full text Add to dashboard Cite

show abstract

“…(Method A, 55%; Method B, 12%) obtained as a white solid; mp 180-190 • C (lit. 30 207-208 • C); IR (cm -1 ) 3441, 2928,1620,1574,1448,1355,1264,820,746; 1 H NMR (400 MHz, CDCl 3 ) d 7.55 (d, J = 1.9 Hz, 1H), 7.52 (d, J = 8.7 Hz, 1H), 7.74-7.17 (m, 7H), 4.63 (s, 2H); 13…”

Section: N-benzyl-6-clorobenzo[d]thiazol-2-amine (5c)mentioning

confidence: 99%

A straightforward synthesis of 2-aminobenzothiazoles from Herz compounds

2011

View full text Add to dashboard Cite

show abstract

“…Eluent: petroleum ether/ethyl acetate (10:1); white solid (82.4 mg, 60%), mp 204–205 °C (lit . 207–208 °C).…”

Section: Methodsmentioning

confidence: 99%

“…17 Hz), 120.2, 122.9 (q, 2 J C−F = 31.7 Hz), 123.427 (q, 3 J C−F = 3.2 Hz), 123.434 (q, 2 J C−F = 31.8 Hz), 124.9 (q, 1 J C−F = 270.2 Hz), 125.1 (q, 1 J C−F = 270.2 Hz), 126.8 (q, 3 J C−F = 4.4 Hz), 131.3, 143.9, 155.1, 164.5. 19 N-Propylbenzo[d]thiazol-2-amine (3l). Eluent: petroleum ether/ ethyl acetate (10:1); white solid (65.4 mg, 68%), mp 77−78 °C (lit.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

Metal-Free Synthesis of 2-Aminobenzothiazoles via Iodine-Catalyzed and Oxygen-Promoted Cascade Reactions of Isothiocyanatobenzenes with Amines

Zhang

et al. 2017

J. Org. Chem.

View full text Add to dashboard Cite

In this paper, a highly efficient and sustainable synthesis of 2-aminobenzothiazoles through the cascade reactions of isothiocyanatobenzenes with primary or secondary amines by using iodine as a catalyst and oxygen as an oxidant is presented. Mechanistically, the formation of the title compounds involves the in situ formation of the required benzothiourea intermediate followed by its intramolecular cross dehydrogenative coupling of a C(sp)-H bond and a S-H bond. To our knowledge, this should be the first example in which 2-aminobenzothiazoles are efficiently prepared from simple and cheap isothiocyanates and amines under metal-free conditions by using iodine as a catalyst and molecular oxygen as an oxidant with water as the byproduct. Compared with literature protocols, this method eliminates the use of ortho-halo-substituted precursors, expensive transition-metal catalysts, and hazardous oxidants.

show abstract

Syntheses of 1,2,4-benzothiadiazine 1-oxides and 1,2,4-benzothiadiazines

Cited by 21 publications

References 0 publications

Experimental and Theoretical Studies of Fused-Ring Persistent [1,2,4]Thiadiazinyl Radicals

Experimental and Theoretical Studies of Fused-Ring Persistent [1,2,4]Thiadiazinyl Radicals

A straightforward synthesis of 2-aminobenzothiazoles from Herz compounds

Metal-Free Synthesis of 2-Aminobenzothiazoles via Iodine-Catalyzed and Oxygen-Promoted Cascade Reactions of Isothiocyanatobenzenes with Amines

Contact Info

Product

Resources

About