A facile route to pyrroles, isoindoles and hetero fused analogues

Expedient synthesis of highly substituted 3,4-dihydro-1,2-oxathiine 2,2-dioxides and 1,2-oxathiine 2,2-dioxides: revisiting sulfene additions to enaminoketones

“…Routine 1 H NMR (400 MHz) and 13 C NMR (100 MHz) spectra were recorded on a Bruker Avance DPX400 instrument in CDCl 3 . Variable Temperature 1 H NMR (500 MHz) and 13 30 (24) and (Z)-3-(hydroxymethylene)-2,2,6-trimethylthiochroman-4-one 31 (25) and isothiochromanone 32 (32) were prepared according to previously reported procedures. 4-(Dimethylamino)-3-(2-fluorophenyl)but-3-en-2-one (15) was prepared according to the procedure described by Kozmin et al, for the preparation of 4-(dimethylamino)-3-phenylbut-3-en-2-one.…”

Green and Efficient Construction of Chromeno[3,4-c]pyrrole Core via Barton–Zard Reaction from 3-Nitro-2H-chromenes and Ethyl Isocyanoacetate

“…Pyrrolocoumarin 4 was synthesized from 4-hydroxycoumarin, triethyl orthoformate and glycine in two steps in an overall yield of 81% [ 6 ]. A similar approach has been used to obtain 4,4-dialkyl-2-acetyl-2,4-dihydrochromeno[3,4- c ]pyrroles from 2,2-dialkyl-4-oxochromane-3-carbaldehydes [ 25 ]. More recently, a copper-catalyzed [1,2]-Stevens-type asymmetric cascade cyclization/rearrangement of OTBS-substituted N -propargyl ynamides to form chromeno[3,4- c ]pyrroles bearing a chiral C-4 stereocenter has been reported [ 26 ].…”

Synthesis of the new ring system 6,8-dihydro-5H-pyrrolo[3,4-h]quinazoline

“…The tetrahydroisoindole-2-one 12a was obtained upon desacetylation by heating in aqueous acetic acid (80%) and HCl (37%) (Scheme 1). 12 Tetrahydroisoindole-4-ones 12b,c were conveniently prepared as described before. 10 Ketones 12a-c were functionalized on the nitrogen atom in THF or DMF using NaH as the base and an alkylating agent such as MeI, BnCl, ClBnpMe, or ClBnpOMe to give the corresponding N-substituted derivatives 13d-o (60-98%).…”