1,3‐Donor/Donor‐substituierte Allene, VI. Umallenierung zu Allen‐1,1‐dicarboxaniliden und deren Thermolyse: Ein direkter Weg zu Polycyclen Kristall‐ und Molekülstruktur von 7‐(Dimethylamino)‐3,4‐dihydro‐N,N‐dimethyl‐5‐oxo‐2H,5H‐pyrano[4,3‐b]pyran‐8‐carboxamid

Abstract

Mit disubstituierten Malonylchloriden 7 erhiilt man aus den leicht darstellbaren iJ-Diethoxy-1,3-bis(anilino)allenen 6 in Abhangigkeit vom Raumanspruch der Substituenten R' und R2 durcb Umalleniencng die AUendianiGde 9 bnv. die Dioxopyrane 8 und 10.Wichtige Folgeprodukte von 10 und 8 b sind die Pyranoderivate 11s (R6ntgenstntkturrUIalyse) und 13. Durcb intramolekulare Diels-Alder-Reaktion von 9c und daraullblgende Isomerisierung

From Push–pull-Substituted Allenes to Tetranuclear Chelate Complexes via Spontaneous Self-Assembly

“…With regard to these considerations, we have paid special attention to the tetradonor-substituted allenes 6, which formally react like the fictitious 1,1-/ 1,3-dianions 8 of malonic esters (R 1 = R 2 = OR) [4,5] or malonic amides (R ] =R 2 =NR2) [6][7][8][9]. In extending the strategy devel- oped for the allenes 6, we have also used the silyl enol ethers 7 of 1,3-dicarbonyl compounds as 1,3-dianion equivalents 8B (R 1 = R 2 = Ph; R^OR, R 2 = Ph) [10].…”

“…As seen for the allene-1,1 -dicarboxamides 25, the allene-1,1-dicarboxanilides 47 are readily available via transallenation from the corresponding l,3-alkylanilino-l,3-diethoxyallenes 46 and the disubstituted malonyl dichlorides 24, with the lactones 48 being formed as by-products (see Schemes 11 and 14) [8]. As seen for the allene-1,1 -dicarboxamides 25, the allene-1,1-dicarboxanilides 47 are readily available via transallenation from the corresponding l,3-alkylanilino-l,3-diethoxyallenes 46 and the disubstituted malonyl dichlorides 24, with the lactones 48 being formed as by-products (see Schemes 11 and 14) [8].…”

“…Thus, when heated in dimethyl sulfoxide at 150° C, this allene 47a forms the intermediate [ [8,39,40]. Thus, when heated in dimethyl sulfoxide at 150° C, this allene 47a forms the intermediate [ [8,39,40].…”

“…As an exception to the above, l,3-bis(7V-phenylanilino)-l,3-diethoxyallene 35, in the presence of diethylmalonyl dichloride 24b, formally eliminates diethylether to afford the Af-phenyl-3-(Af-phenylanilino)propynoic acid anilide 36, in a 60 % yield [8]. Scheme 19…”

Computational and Experimental Investigations of the Formal Dyotropic Rearrangements of Himbert Arene/Allene Cycloadducts

“…Highlighted entries are for krel < 1 (red), krel ≅1 (yellow), krel >> 1 (green the conditions used to effect cycloaddition; the initial cycloadduct could not be isolated. 23 However, the tertiary amide group and allene substitution likely conspire to depress the rate of the IMDA reaction, requiring 150 °C to effect cycloaddition (compared to the 130 °C in prior cases). At this temperature, the dyotropic rearrangement occurs spontaneously and only isomerized bicyclo[3.2.1]octadiene was isolated.…”