Heterocyclen mit endocyclischer Schwefel‐Stickstoff‐Doppelbindung, II. 1‐Substituierte 3.4‐Dihydro‐1H‐1.2.4‐benzothiadiazin‐3‐one und 1‐substituierte 3.4‐Dihydro‐1H‐1.2.4‐benzothiadiazin‐3‐on‐1‐oxyde

Abstract

Durch dehydrierende Cyclisierung von 2-Alkylmercapto-und 2-Arylmercaptophenylharnstoffen werden I-substituierte 3.4-Dihydro-1 H-1.2.4-benzothiadiazin-3-one (XIII) gewonnen. Diese lassen sich mit Kaliumpermanganat zu den I-substituierten 3.4-Dihydro-l H-l.2.4-benzothiadiazin-3-on-l-oxyden (XIV) oxydieren. Vom 1.2.4-Benzothiadiazin lassen sich drei tautomere Strukturen (I, I1 und 111) formulieren. Verbindungen, die sich vom 2 H-1.2.4-Benzothiadiazin (11) ableiten, wurden erstmals von EKBOM 2) dargestellt. Diese 2H-1.2.4-Benzothiadiazin-1.l-dioxyde (IV, R = H und Methyl) sind in waflrigem Alkali loslich und konnen in 2-Stellung methyliert werden. SCHRADER3) fand beim CuRTrus-Abbau des o-Sulfamyl-benzazids das 3.4-Dihydro-2 H-1.2.4-benzothiadiazin-3-011-1.1 -dioxyd (V). WERTHEIM 4) erhielt durch Erhitzen des N-[o-Amino-benzolsulfonyll-benzamids das 3-Phenyl-2H-1.2.4-benzothiadiazin-1 .I-dioxyd (IV, R = Phenyl). 3-Methyl-2H-1.2.4-benzothiadiazin-l . I-dioxyd (IV, R = Methyl) kann auch durch Reduktion des N-Acetyl-o-nitro-benzolsulfonamids erhalten werden5). Nachdem WILLIAMS^) bei Kaninchen nach Orthanilamid-Gaben geringe Mengen 1V (R = Methyl) isolieren konnte, haben sich PARKE und WILLIAMST) eingehender mit der Synthese von 1.2.4-Benzothiadiazin-I . I-dioxyden befaBt und eine Reihe auch im aromatischen Kern *) Teil der Dissertation G.

Rhodium‐Catalyzed ortho‐Amidations in the Preparation of Thiadiazine 1‐Oxides

“…The first derivatives of thiadiazine 1‐oxides were reported by Wagner and Reinöhl as early as 1964 . A few years later, Williams and Cram, as well as industrial colleagues at Beiersdorf and Gödecke, developed new synthetic strategies towards such compounds.…”

“…Commonly, thiadiazine‐1‐oxides 1 are prepared by multiple‐step syntheses starting from N‐protected 2‐thio‐substituted anilines or ortho ‐nitroaryl thioethers . With the goal of easing access to such interesting compounds and being inspired by our previous work in this area, we wondered about an alternative strategy starting from readily available, commercial sulfoximines 5 .…”

“…General procedure for the palladium-catalyzedcross-coupling AS chlenk tube (25 mL) was charged with 1-methyl-3-(methylthio)benzo[e] [1,2,4]thiadiazine 1-oxide (10,4 5.2 mg, 0.20 mmol), the boronic acid (0.22 mmol), [Pd 2 dba 3 ](7.3 mg, 0.0080 mmol), tri(2-furyl)phosphine (7.4 mg, 0.032 mmol), and CuTC (49.7 mg, 0.26 mmol). Under an argon atmosphere, dry THF (2.0 mL) was added to the mixture by syringe.…”

Syntheses and Transformations of Sulfoximines

“…In 1964, Wagner and Reinçhl reported the first derivatives of thiadiazine 1‐oxides [89] . A few years later, Williams and Cram [90] as well as industrial colleagues at Beiersdorf [91] and Gödecke [92] developed new strategies for synthesizing such compounds.…”

Iridium(III)-Catalyzed C–H Amidation/Cyclization of NH-Sulfoximines with N-Alkoxyamides: Formation of Thiadiazine 1-Oxides

“…Thiadiazine 1-oxides as abundant cores of nitrogen-containing heterocycles, such as NSC 287474, Gö 4962, and an analog of prazosin, were found to bear diverse biological and therapeutic activities . Despite the strong attraction to these particular units, applicable approaches to synthesize benzothiadiazine skeletons are rather limited and hence are highly desirable. , Over the past few decades, transition-metal-catalyzed C–H activation has attracted great attention because of its high efficiency, reactivity, and atom-economical properties and even its ability to synthesize complex compounds .…”