AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Palladium(II) salts catalyse stereospecific and highly facially selective oxime-nitrone-isoxazolidine cascade reactions between alpha-imino aldoximes and N-methylmaleimide via intermediate N-metallo-aldonitrones. These processes occur at room temperature in a range of polar solvents through the chelation of both alpha-imino and aldoxime nitrogen atoms to the palladium (II) centre. (C) 1997 Elsevier Science Ltd.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Reaction of 1-methyl-,1-benzyl- and 1-benzoyl-4-ethoxycarbonylpyridinium salts I with zinc and benzyl bromide produce regioselectively the 4,4-disubstituted 1,4-dihydropyridines 3 (R = CH3, PhCH(2), PhCO); only the latter is stable but all are reduced catalytically to piperidines 2 (R = CH3, PhCH(2), PhCO). 1-Benzoyl-4-ethoxycarbonylpyridinium chloride with zinc and benzoyl chloride or ethyl bromoacetate gives respectively 4-benzoyl-18 or 4-ethoxycarbonylmethyl-1-benzoyl-4-ethoxycarbonyl 1,4-dihydropyridine 17, but 1-methyl-4-ethoxycarbonylpyridinium iodide 1 (R = CH3, X =: I) with benzoyl chloride gives 3-benzoyl-4-ethoxycarbonyl-1-methyl-1,2-dihydropyridine 21. The action of zinc and benzyl bromide on 1-methyl- and 1-benzyl-3-ethoxycarbonylpyridinium salts 5 gives, after catalytic hydrogenation, mixtures of 2- and 4-benzyl-5-ethoxycarbonyl-1,2,3,4-tetrahydropyridines 6 and 7 (R CH, or PhCH,) but similar treatment of 1-benzoyl-3-ethoxycarbonylpyridinium chloride 5 (R = PhCO, X = Cl) yields selectively the stable 4-benzyl-3-ethoxycarbonyl-1,4-dihydropyridine. 9. Treatment of 1-methyl- or 1-benzoyl-3-ethoxycarbonylpyridinium salts 5 with zinc and benzoyl chloride gives a mixture of products, 1-Methyl-2-ethoxycarbonylpyridinium iodide 11 (R 3 CH3, X = I) reacts with zinc-and benzyl bromide giving, after catalytic hydrogenation, 2-, 4- and 6-benzyl-2-ethoxycarbonyl-1-methylpiperidines 12, 13 and 14(R = CH3) in the ratio 2:7: 1, but 1-benzyl-2-ethoxycarbonylpyridinium bromide 11 (R = PhCH(2), X = Br) gives only 1,4-dibenzyl-2-ethoxycarbonylpiperidine 13(R = PhCH(2)).

4-Benzyl-4-ethoxycarbonyl-1-substituted piperidines 1 (R(1) = PhCH(2), PhCO; R(2) = PhCH(2)) cyclise with polyphosphoric acid (PPA) to give spiro [indane-2,4'-piperidin]-1-ones 3 (R = PhCH,, PhCO), while 2-benzyl-2-ethoxycarbonyl-1-methylpiperidine 4 gives the N-methylspiro [indane-2,2'-piperidin]-1-one 5. 3,4,4a, 5-Tetrahydrobenz[g]isoquinolin-10(2H)-one 8 arises from PPA treatment of 1-benzoyl-4-benzyl-5-ethoxycarbonyl-1,2,3,4-tetrahydropyridine 7 (R = PhCO) while o-chloranil converts 1-benzoyl-4-benzyl-4-ethoxycarbonyl 1,4-dihydropyridine 6 (R = PhCO) into 4-benzyl-3-ethoxycarbonylpyridine 9. Phenyl(tribromomethyl)mercury reacts with 1-benzoyl-4-benzyl-4-ethoxycarbonyl-1,4-dihydropyridine 2 (R(1) = PhCO, R(2) = PhCH(2)) yielding 2-benzoyl-5-benzyl-7,7-dibromo-5-ethoxycarbonyl-2-azabicyclo[4.1.0] hept-3-ene 11, and with 1-benzoyl-4-benzyl-3-ethoxycarbonyl-1,4-dihydropyridine 6 (R = PhCO) to give 2-benzoyl-5-benzyl-7,7-dibromo-4-ethoxycarbonyl-2-azabicyclo[4.1.0]hept-3-ene 12, The structure of the latter is confirmed by X-ray crystallographic analysis. Catalytic hydrogenation of 2-benzoyl-5-benzyl-7,7-dichloro-5-ethoxyca [4,1,0]hept-3-ene 16 yields 2-benzoyl-5-benzyl-7,7-dichloro-4-ethoxycarbonyl-2-azabicyclo [4,1,0]heptane 21 which cyclises with PPA to give the tetracyclic product 22 in good yield, When 2-benzoy-5-benzyl-7,7-dichloro-4-ethoxycarbonyl azabicyclo[4.1.0] hept-3-ene 17 is hydrogenated it yields mainly 2-benzoyl-5-benzyl-7,7-dichloro-4-ethoxycarbonyl-2-azabicyclo[4. 1.0]heptane 25 but the dibromo analogue 12 under the same conditions gives two components thought to be 2-benzoyl-5-benzyl-7-endo-bromo-4-ethoxycarbonyl-2- azabicyclo [4.1.0]hept-3-ene 24 and 2-benzoy-5-benzyl-7-exo-bromo-4-ethoxycarbonyl-2-azabicyclo[4,1,0] hept-3-ene 23.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Metallo - 1,3-dipoles generated in situ from both aryl and aliphatic imines of a-amino esters by the action of silver salts and tertiary amines undergo cycloaddition at room temperature to 5R-(1'R, 2'S, 5'R-menthyloxyl) - 2(5H)-furanone and to N-acetyl-5R-isopropoxy-2(5H)-pyrrolone giving homochiral cycloadducts in good yield in all cases. pi-Interaction between the dipolarophile carbonyl group and the aryl group in the aryl imines is not required for good induction. The stronger the base the faster the cycloaddition with 2-t-butyl-1,1,3,3-tetramethylguanidine > DBU > NEt(3). X-Ray crystal structures of representative cycloadducts establish the absolute configuration of the pyrrolidine stereocentres.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The title compound, C11H16N+.Cl-, packs to give non-polar and polar regions in the crystal. In the polar region each proton of the NH3+ group points towards a Cl- ion; the average N...Cl separation is 3.183 angstrom.

2-Chloro-N-tosylprop-2-enylamine (5; R = H) was converted into methyl 3-[N-(2-chloroprop-2-enyl)-N-tosylamino]propanoate (5; R = CH2CH2CO2Me) and into 3-[N-(2-chloroprop-2-enyl)-N-tosyl-amino]propanonitrile (5; R = CH2CH2CN). These, in turn, were converted into 4-[N-(2-chloroprop-2-enyl)-N-tosylamino]-1-methylbutan-2-ol [5; R = CH2CH2C(OH)Me2], 3-[N-(2-chloroprop-2-enyl)-N-tosylamino]-1-phenylpropan-1-one (5; R = CH2CH2COPh), 4-[N-(2-chloroprop-2-enyl)-N-tosylamino]-2-phenylbutan-2-ol [5; R = CH2CH2C(OH)(Me)Ph], 3-[N-(2-chloroprop-2-enyl)-N-tosylamino]-1-phenylpropan-1-ol [5; R = CH2CH2CH(OH)Ph], 4-[N-(2-chloroprop-2-enyl)-N-tosylamino]butan-2-ol [5; R = CH2CH2CH(OH)Me] and 3-[N-(2-chloroprop-2-enyl)-N-tosylamino]propanoic acid (5; R = CH2CH2CO2H). The alcohols [5; R = CH2CH2C(OH)Me2] and [5; R = CH2CH2CH(OH)Ph] were cyclised by 90% sulfuric acid to 5,5-dimethyl-N-tosylazepan-3-one (6; R1= R2= Me) and 5-phenyl-N-tosylazepan-3-one (6; R1= Ph, R2= H), respectively. 6,6-Dichloro-N-tosylazepan-4-one 7 was obtained from 3-[N-(2-chloroprop-2-enyl)-N-tosylamino]propanoic acid (5; R = CH2CH2CO2H)via the acid chloride and was further converted into 6-chloro-1,2,3,7-tetrahydro-N-tosylazepin-4-one (8, R = Cl) and into the 6-methoxy analogue (8; R = OMe).

AbstractRing expansion of the tetralone derivative (I) is only achieved with the carboxylate (I), giving the benzocyclooctene (III) in poor yield.

C 13 H 15 ClN + •Cl − •1.5H 2 O cristallise dans le systeme triclinique, groupe d'espace P1 et sa structure est affinee jusqu'a R=0,051. Il y a deux cations independants dans l'unite asymetrique, avec des dimensions tres similaires

C 21 H 13 ClO 2 cristallise dans le systeme monoclinique avec le groupe d'espace P2 1 /n. Affinement de la structure jusqu'a 0,060