1,3‐Donor/Donor‐substituierte Allene, VII Allencarboxanilide durch Umallenierung oder [2.3]/[3.3]1‐sigmatrope Umlagerungen Bausteine mit vielseitigem intra‐und intermolekularem Synthesepotential

Abstract

1.3-Donor/Donor-Substituted Allenes, VII1ll. -Allenecarboxanilides by Transallenation or [2.3]/[3.3]-SigmatropicRearrangements -Building Blocks with Versatile Intra-and Intermolecular Synthetic Potential*The reaction of 1,3-bis(alkylarylamino)-1,3-diethoxyallenes 1, 2 with disubstituted malonyl chlorides 3 leads to N,N-dialkyl-N,N-diarylallene-1,l-dicarboxamides 4, 5, and 2H-pyran-2,4(3H)-diones 6, 7, respectively, with a transallenation reaction being favoured in the case of allene 1. Thermal tandem cyclisation of allene-1,l-dicarboxanilide 4c via 2-quinolone 8 affords phenanthridone 9. Spontaneous acylcycloalkanelcycloenol ether isomerisation of spirane 6b gives pyrane 12. Thermally induced (Z)-anilinoacrylic acidlquinolone cyclisation of pyranes 6a, 12, and 7 leads to 4-quinolones 11,13, and 14. Propargyl THP ether 15 reacts with carbamoyl chloride 16 to yield alkinol-N-phenylanilides 17. Alkinol 17a reacts with sulfinyl chloride 18 to yield sulfinic ester 19, which on heating undergoes a [2.3]-sigmatropic rearrangement to N-phenyl-lsulfonylallene-1-carboxanilide 20. Reaction of alkinols 17 with sulfenyl chlorides 21 or chlorophosphanes 23, followed by [2.3]-sigmatropic shift, affords N-phenyl-1-sulfinyl-22 and Nphenyl-1-phosphorylallene-1-carboxanilides 24, respectively. Alkinyl ketene acetal intermediates 26 are formed starting from alkinol 17 a and orthoesters 25. Spontaneous (3.31-sigmatropic rearrangement of 26 gives N-phenylallene-l-carboxanilides 27. Intramolecular Diels-Alder (IDA) reactions of the allene-1-carboxanilides 27 lead to (2.2.2lbicycles 28. Contrarily, the IDA intermediates of 20 b and 24 further isomerize to the [3.2.l]bicycles 29 and 30. The allenyl sulfoxides 22 readily undergo Michael-type reactions with CH-acidic compounds 31 to give ally1 sulfoxides 32. Among these, only 32d can be isolated, whereas 32a-c spontaneously rearrange in a fourstep reaction cascade to butenolides 33a-c. A Michael-type reaction of (diethoxyphosphory1)allenes 24 with whydroxy ketones 34 followed by a Horner-Emmons reaction leads to alkylidene-dihydro-furans 35, which isomerize in the presence of a base to yield furans 36. Analogously, allenes 24 react with 2-hydroxybenzaldehydes 37 or 2-pyrrole-/2-imidazole derivatives 40 to form alkylidenechromenes 38 and pyrrolizines/ pyrroloimidazoles 41, respectively. Benzopyrylium salts 39 are accessible from chromenes 38 and perchloric acid.Die Umsetzung von 1,3-Bis(alkylarylamino)-1,3-diethoxyallenen mit disubstituierten Malonylchloriden liefert

Roots: From carbenes to allenes and coordination polymers : Ever present never twice the same

“…Similarly, the allenecarboxanilides 62a, 63a and 64a on heating undergo intramolecular Diels-Alder reactions and isomerization to give the [3.2.1]-bicycles 76, 77 and 78 in good yields (60-70%). 50,51 It is worthy noting, however, that we succeeded only in the case of N-phenyl-allene-1-carboxanilide 67 to isolate the initial [2.2.2]-bicyclic Diels-Alder product 79 51 (Scheme 23).…”

“…Allenecarboxanilides generally undergo intramolecular Diels-Alder reactions. 50,51,[64][65][66][67] This is also true for the readily available allene-1,1-dicarboxanilides 51f, 62a-64a and 67. For instance, when N,N9-dimethyl-allene-1,1-dicarboxanilide 51f is heated neat or in DMSO to 150-200 uC, an intramolecular Diels-Alder reaction of the N-phenyl ring and the terminal allene double bond generates the [2.2.2]-bicycle 74, which spontaneously isomerizes to give [3.2.1]-bicycle 75.…”

“…48,49 The readily accessible tetradonor allenes 50 react with disubstituted malonyl chlorides, via transallenation, to give allene-1,1-dicarboxamides 51. 48,50,51 Previously, transallenation has not played a significant role in allene chemistry. This novel method is of general use if attention is paid to ensuring that suitable substituent combinations are used.…”

“…54 Alkynol-N-diphenylanilides 58 and diethyl hydroxyalkynylphosphonates 59 can be obtained by protection of the alkynols 57 with dihydropyrane (DHP), deprotonation with n BuLi, reaction of the acetylides thus generated with diphenylcarbamoyl chloride or phosphoric acid diethylester chloride, and a subsequent acidic hydrolysis. 51,55 Reaction of the alkynols 57 with alkaline sodium hypochlorite or potassium hypochlorite solutions leads to the halo alkynols 60 56 via proton/halogen exchange (Scheme 17).…”

“…The reaction sequence Michael addition/Horner-Emmons reaction proceeds even with a-hydroxylactones, as demonstrated by the formation of alkylidene dihydrofuran 89. 51 Similarly, allylic sulfoxides such as 61a react with CH-acidic compounds in the presence of sodium hydride, with subsequent protonation giving Michael products 90 after the first step (Scheme 26). These allylic sulfoxides readily undergo a two step reaction cascade ([2.3]-sigmatropic shift, sulfenic acid ester/butyrolactonization) to generate the lactones 92 via 91 and a subsequent cyclization.…”