0000000000177616
AUTHOR
Dieter Gröschl
showing 11 related works from this author
Cycloaddition Reactions of 2H-Benzo[b]thiete and Thiocarbonyl Compounds
1997
2H-Benzo[b]thiete (1) reacts in the o-quinoid form 1′ with the cyclic trithiocarbonates 4 and 6a, b and with the thioketones 8, 10 and 12 in [8π + 2π] cycloaddition reactions to the spiro compounds 5, 7a, b, 9, 11a, b. Irrespective of the presence of CC double bonds, chemoselective and regioselective addition processes at the CS double bonds take place that lead to 4H-1,3-benzodithianes.
Cycloaddition reactions of 2H-benzo[b]thiete and conjugated cyclic dienes
1996
2H-Benzo[b]thiete 1 reacts with cyclopentadiene 3 in consecutive [8π + 2π]cycloadditions yielding the condensed heterocycles 6–8. Tetracyclone 9 on the other hand gives only the monoadduct 10. An [8π + 8π]cycloaddition can be observed for 1 and diphenylisobenzofuran 11. The related π system 13 shows again consecutive [477π + 27π]processes (1 + 13 ← 14, 15).
Thermal rearrangements of 1,2-dialkoxybenzenes by flash vacuum pyrolysis
1995
Flash vacuum pyrolysis of 1,2-dialkoxybenzenes 1a-c leads to the liberation of alkanes from the interacting side chains. A rearrangement of the skeleton yields the o-hydroxy carbonyl compounds 2 and 4. The generation of phenol 3 can be rationalized by a decarbonylation. The latter reaction is the sole process which can be observed for the bicyclic starting compound 9.
Crystal structure of a dimeric 1-benzothiepin
2016
AbstractThe crystal structure of the 1-benzothiepin derivativemeso-5is presented. Compound5is the first dimeric 1-benzothiepin system.
Reaction of 2H-1-benzothiete with diazo compounds in the presence of rhodium(II) acetate
1995
2,3-Dihydrobenzo[b]thiophenes (7a-e) were prepared by the Rh2+ catalyzed reaction of 2H-1-benzothiete (1) and diazo compounds (3a-e). α,β-Unsaturated diazo esters (3b,e) and diazo ketones (3d,e) yielded additionally 4,5-dihydro-1-benzothiepins (11b,c) and 5H-4,1-benzoxathiepins (12d,e), respectively.
ChemInform Abstract: Benzothietes. Versatile Synthons for the Preparation of Heterocycles
2010
Abstract Thermal or photochemical ring opening transforms benzo[b]thiete to o-thiobenzoquinonemethide, a highly reactive 8π electron system. Cycloaddition reactions or linear additions with subsequent cyclizations lead to larger heterocyclic rings. A variety of compounds containing sulfur and possibly further heteroatoms like nitrogen, oxygen or phosphorus in normal, medium and large ring systems can be synthesized on this route.
An alternative route to 2H-naphtho[1,2-b]thiete and its cycloaddition products
1998
2-(1H-Benzotriazol-1-ylmethyl)-1-naphthalenol (1) can be transformed in high yields to the corresponding thiol 4. Flash vacuum pyrolysis of 4 leads to 2H-naphtho[1,2-b]thiete (5). The benzotriazolyl group proved to be a good leaving group; however, a subsequent nitrogen extrusion takes place under flash vacuum pyrolysis conditions and cyclopentadienecarbonitriles 6a,b are formed by a ring contraction (Scheme 1). Cycloaddition reactions of 5 and dienophiles or heterodienophiles yield the naphtho-condensed sulfur heterocycles 8, 10, 12 and 14 (Scheme 2).
Cycloaddition reactions of 2H-1-benzothietes and 1,3,5,7-tetrathio-s-indacene-2,6-dithiones
2016
Abstract 2H-1-benzothiete (1) and 2H,5H-benzo[1,2-b:4,5-b′]bisthiete (3) react in form of their open valence isomers with the trithiocarbonic acid esters 2a–c. The one- or twofold cycloaddition reactions yield 1,3-dithiin rings, in which C-2 is a spiro-C atom, that bears four sulfur groups. The bifunctional reactant 3 gives additionally band-shaped, hardly soluble oligomers.
BENZOTHIETES—VERSATILE SYNTHONS FOR THE PREPARATION OF HETEROCYCLES
1994
Abstract Thermal or photochemical ring opening transforms benzo[b]thiete to o-thiobenzoquinonemethide, a highly reactive 8π electron system. Cycloaddition reactions or linear additions with subsequent cyclizations lead to larger heterocyclic rings. A variety of compounds containing sulfur and possibly further heteroatoms like nitrogen, oxygen or phosphorus in normal, medium and large ring systems can be synthesized on this route.
Synthese von Benzo[b]thioxanthenen
1995
Synthesis of Benzo[b]thioxanthenes Benzo[b]thioxanthenes, heterocyclic compounds related to tetracenes and tetracyclines can be obtained by the reaction of 2H-benzo[b]thiete (1) and 1,4-naphthoquinones (3a–g). The primary cycloadducts 4a–g undergo an autoxidation process leading to the quinones 6a–g. The dihydroxy compound 4e shows an additional isomerization by a tetrafold H transfer (4e 5e′). Another preparative route to benzo[b]thioxanthenes makes use of the cycloadditon reaction of 1 and 1,4-epoxynaphthalenes (7a–d). The primary adducts can be transformed to the title compounds by catalytic dehydration processes (8a–d 9a-d). An alternate regioselective opening of the oxygen bridge can b…
Cycloadditionen von 2H ‐Benzo[ b ]thiet und Verbindungen mit kumulierten Doppelbindungen
1994
Cycloaddition Reactions of 2H-Benzo[b]thiete and Compounds with Cumulated Double Bonds o-Thiobenzoquinone methide (2), generated by thermal ring opening of 2H-benzo[b]thiete (1), reacts with allene 3, ketene imine 7, the carbodiimides 9a-c, and the N-sulfinylamines 11a-c in highly specific [8π + 2π] cycloaddition processes to form novel types of heterocyclic systems 4, 8, 10a-c, and 12a-c with exocyclic double bonds. The 1:1 adduct 4 can add a further molecule of allene to yield the spiro compounds 5 and 6.