Showing papers on "Piperidine published in 1972"
TL;DR: In this paper, it was shown that 3-chloro-1-ethylpiperidine undergoes nucleophilic displacement reactions in solution by a two-step, neighboring group participation mechanism.
78 citations
28 citations
TL;DR: The carbon-13 chemical shifts of a number of piperidine and piperazine compounds have been measured as discussed by the authors, and substitutive parameters for methyl groups bonded to carbon and nitrogen have been derived from the symmetrically substituted compounds and used to predict results for unsymmetrical compounds in good agreement with experimental values.
Abstract: The carbon-13 chemical shifts of a number of piperidine and piperazine compounds have been measured. Substituent parameters have been derived, for methyl groups bonded to carbon and nitrogen, from the symmetrically substituted compounds and used to predict results for unsymmetrical compounds in good agreement with experimental values.
20 citations
TL;DR: The bis(β-ketoenolates)nickel(II) adducts of piperidine, piperazine, methylpiperazine and morpholine were isolated in the solid state and investigated by magnetic measurements and electronic and optical sensors.
Abstract: The bis(β-ketoenolates)nickel(II) adducts of piperidine, piperazine, methylpiperazine, and morpholine are isolated in the solid state and investigated by magnetic measurements and electronic and i....
20 citations
Patent•
27 Jun 1972
TL;DR: Piperidine-spiro-hydantoin derivatives have the formula (SPC1) where X represents oxygen atom or sulfur atom; n is an integer of 1 to 4 inclusive, and R represents various aliphatic or aromatic groups depending on the value of n.
Abstract: Piperidine-spiro-hydantoin derivatives having the formula ##SPC1## Wherein X represents oxygen atom or sulfur atom; n is an integer of 1 to 4 inclusive, and R represents various aliphatic or aromatic groups depending on the value of n. These compounds (I) are useful as stabilizers against photo and thermal deterioration of various synthetic polymers and can be prepared, for example, by reacting the corresponding 3-unsubstituted piperidine-spiro-hydantoin compound with the halide R-(X1)n in which R and n are as defined herein and X1 is a halogen atom.
17 citations
TL;DR: In this paper, it was shown that phenacyl cyanide also reacts with dimethyl phosphite to give the corresponding dimethyl (α-cyanomethyl) α-hydroxy benzyl phosphonate.
17 citations
15 citations
TL;DR: In this article, the rearrangement of N-benzoyl2-pyrrolidone(1) to 2-phenylpyrroline (2) provided us with an imaginative heuristic upon which some novel entries into the pyrrolidine and piperdine alkaloids was based.
15 citations
TL;DR: In this paper, the two stereoisomeric 4-t-butyl-N-methylpiperidine-Noxides were prepared by oxidizing 4-T butyl N-methyl piperidine.
13 citations
TL;DR: Perfluoro-(2-isopropylpyridine) can be prepared from perfluoro-N-fluoropiperidine in three separate stages according to this scheme, which exemplifies a possible useful route to 2-substituted tetrafluoropyridines.
Abstract: Photolysis of perfluoro-N-fluoropiperidine in the presence of perfluoropropene gives perfluoro-(2-methylpentane), perfluoro-(2,3-dimethylbutane), perfluoro-(N-propylpiperidine). perfluoro-(N-isopropylpiperidine), perfluoro-[N-(1,3-dimethylbutyl)piperidine], a 2:2 adduct (2C5F10NF:2C3F6), and perfluoro-NN′-bipiperidyl. Thermal reaction of perfluoro-N-fluoropiperidine with perfluoropropene in stainless steel in the presence of caesium fluoride yields, inter alia, perfluoro-(2-isopropyl-3,4,5,6-tetrahydropyridine) and perfluoro-(2-isopropylpyridine); this conversion is believed to involve defluorination of the piperidine to perfluoro-2,3,4,5-tetrahydropyridine followed by attack on this product by perfluoroisopropyl anion and subsequent aromatisation of perfluoro-(2-isopropyl-3,4,5,6-tetrahydropyridine) thus formed. Perfluoro-(2-isopropylpyridine) can be prepared from perfluoro-N-fluoropiperidine in three separate stages according to this scheme, which exemplifies a possible useful route to 2-substituted tetrafluoropyridines.
13 citations
TL;DR: Results support Spenser's hypothesis that pipecolic acid and the piperidine alkaloids derived from lysine do not have 6-amino-2-ketohexonoic acid as a common intermediate.
TL;DR: In this article, the absorption of dioxane, morpholine and piperidine from dilute aqueous solutions by Li-, Ca-, and Cu-montmorillonite is measured by means of a differential refractometer.
Abstract: The absorption of dioxane, morpholine and piperidine from dilute aqueous solutions by Li-, Ca-, and Cu-montmorillonite is measured by means of a differential refractometer. This instru- ment measures small differences in the refractive indices of two liquids and provides a useful method for determining the amount of organic material removed from solution by the clay. Corrections are required for the effect of desorbed cations on the differential refraction measurements. Neutral molecules are absorbed in amounts related to the exchange capacity of the clay probably by cation- dipole interactions. The results are consistent with the formation of complexes Li+-R and R-Ca2+-R R 2+ 2+ for the three organic materials used; Cu ions behave like Ca ions for dioxane, but form > Cu2+-R R complexes with morpholine and piperidine. Under acid conditions, morpholine and piperidine form organic cations RH + which take part in cation exchange reactions and which are dominant at pH below about 5. Neutral molecule absorption also occurs by virtue of the presence of RH + ions on the clay which form RH+-R complexes (hemi-salt formation). When this last mechanism of absorption occurs, the total absorption is approximately twice that when a cation-dipole reaction or cation exchange alone operates. One-dimensional Fourier 001 syntheses of complexes in equilibrium with aqueous organic solutions indicate that water molecules are associated with the clay-organic com- plexes to the extent of about 5H20/unit cell.
TL;DR: The reaction of trans-3,4-dibromotetrahydro-3 4-bis-(methylamino)thiophen dioxide with methylamine gave perhydro-1,3-dimethyl-trans-thieno-[3, 4]-imidazol-2-one SS-dioxide (3; R = Me), which was studied by X-ray crystallography as mentioned in this paper.
Abstract: Reaction of trans-3,4-dibromotetrahydrothiophen dioxide with methylamine affords trans-tetrahydro-3 4-bis-(methylamino)thiophen dioxide. Reaction with phosgene then gave perhydro-1,3-dimethyl-trans-thieno-[3,4-d]imidazol-2-one SS-dioxide (3; R = Me), which was studied by X-ray crystallography. [Crystal data: a= 8.616(3), b= 15.280(5), c= 7.409(3)Aβ= 102.62(4)°, space group C2/c,Z= 4]. Ammonia gave a similar product. Piperidine also reacted with the dibromide to give the corresponding diamine, whereas pyridine afforded a novel pyridinium salt.
Patent•
27 Nov 1972
TL;DR: A synthetic polymer composition stabilized against photo and thermal deterioration is disclosed by incorporating in the composition an effective amount of defined N-substituted piperidine derivatives as discussed by the authors, where the stabilization is obtained by incorporating a composition that consists of
Abstract: A synthetic polymer composition stabilized against photo- and thermal deterioration is disclosed. The stabilization is obtained by incorporating in the composition an effective amount of defined N-substituted piperidine derivatives.
TL;DR: The reaction of piperidine with 1,2,4-trinitrobenzene or with o-dinitronzene in benzene has been studied in this paper.
Abstract: The reaction of piperidine with 1,2,4-trinitrobenzene or with o-dinitrobenzene in benzene affords 2,4-dinitro-1-piperidinobenzene or 2-nitro-1-piperidinobenzene, respectively, in quantitative yield. Neither reaction undergoes base catalysis and overall second-order kinetics (first-order with respect to each reagent) were observed for a wide range of piperidine concentrations in benzene. Acid catalysis does not occur either as added p-methoxyphenol fails to affect appreciably the kinetics of the reaction of the trinitrobenzene. Comparison with the reaction of piperidine with 1-fluoro-2,4-dinitrobenzene in benzene, where pronounced catalysis by both piperidine and p-methoxyphenol has been observed, allows an interpretation of the reaction in terms of an addition–elimination mechanism with rapid expulsion of the nitro-group from the intermediate. Why the expulsion of the nitro-group from the intermediate should occur so easily is not clear, however. The recent literature concerning the nucleophilic aromatic substitution of the nitro-group is reviewed.
TL;DR: In this article, the magnetic properties of amine adducts of uranium tetrachloride and tetrabromide with aromatic, alicyclic, and aliphatic amines were investigated.
Abstract: Electronic spectra and magnetic measurements are reported for some new adducts of uranium tetrachloride and uranium tetrabromide with aromatic, alicyclic, and aliphatic amines; and for some previously reported amine adducts of uranium tetrachloride and also for the compound [(Et4N)4][U(NCS)8] in which the anion has a cubical configuration. The data suggest that the adducts with pyridine and piperidine may have an unusual configuration.
TL;DR: In this paper, spectral features of three diastereoisomeric 1,2,5-trimethyl-4-phenylpiperidin-4ols are reported and shown to provide evidence of the configurations t-2-Me,c-5-me,r- 4-OH (γ-isomer), t- 2-Me and c-2 -me,t-5 -me-r-4 -OH (β-isomers).
Abstract: Some 1H n.m.r. spectral features of three diastereoisomeric 1,2,5-trimethyl-4-phenylpiperidin-4-ols are reported and shown to provide evidence of the configurations t-2-Me,c-5-Me,r-4-OH (γ-isomer), t-2-Me,t-5-Me-r-4-OH (β-isomer), and c-2-Me,t-5-Me,r-4-OH (α-isomer). Evidence is given that significant skew-boat populations (with the 4-phenyl group pseudoequatorial) arise in the case of the α-alcohol as solute in deuteriochloroform, while preferred conformations of the γ- and β-isomers are piperidine chairs with the 4-phenyl group equatorial. Stable epimeric conjugate acids of the β-hydrochloride were detected in deuterium oxide. Present findings are compared with those of previous studies.
TL;DR: In this article, secondary amines add across the free ethynyl group of unsubstituted diacetylenic ketones and strong solvent-induced shifts, of up to 40 nm, are observed in the u.v. spectra of the adducts.
Abstract: Secondary amines add across the free ethynyl group of unsubstituted diacetylenic ketones. Reactions of piperidine with 1-phenylhexa-2,4-diyn-1-one (7), a methyl-substituted derivative, afford 1-phenyl-5-piperidinohex-4-en-2-yn-1-one (17), 3,5-dipiperidinobiphenyl (20), and a diadduct (21); in the presence of water 1-phenyl-3-piperidino-hex-2-ene-1,5-dione (27) is also obtained. Strong solvent-induced shifts, of up to 40 nm, are observed in the u.v. spectra of the adducts. Some unstable alkyl diacetylenic ketones [(4)–(6)] have been obtained.
TL;DR: The mercuric acetate-(ethylenedinitrilo) tetraacetic acid oxidation of aminoalcohol III furnished lactamalcohol V in 73% yield and its O-acetyl derivative (VI) as a minor product.
Abstract: The mercuric acetate-(ethylenedinitrilo) tetraacetic acid oxidation of aminoalcohol III furnished lactamalcohol V in 73% yield and its O-acetyl derivative (VI) as a minor product. Treatment of V with phosphoryl chloride gave tetrahydrobenzo [α] quinolizinium salt X in 87% yield, whereas hydrogenolysis of V in the presence of perchloric acid and ring-closure of the resulting lactam VIII afforded hexahydrobenzo [α] quinolizinium salt IX, which produced benzo [α] quinolizidine Ia on hydrogenation. When treated with perchlo-ric acid, lactamalcohol V yielded oxazolinium salt VIIa in a good yield. The facile hydrogenolysis of VIIa to VIII has suggested the possibility that the perchloric acid-accelerated, direct hydrogenolysis of V may proceed through VIIa. The starting aminoalcohol III was synthesized either by the sodium borohydride reduction of aminoketone II obtained from piperidine and 3, 4-dimethoxyphenacyl bromide or by reduction of quaternary salt IV from pyridine and 3, 4-dimethoxyphenacyl bromide.
TL;DR: In this article, the synthesis and conformational analysis of -5(Benzyloxycarbonylamino)-5.6-dideoxy-β-L-idopyranose is presented.
Abstract: 5-Benzyloxycarbonylamino-5.6-didesoxy-β-L-idose liegt in einem Gleichgewicht zwischen Furanose 4 und Piperidin-Form 5 im Verhaltnis 1 : 4 vor. Nach den NMR-Daten bevorzugen die Piperidin-Zucker 6 und 7 weitgehend die Cl(L)-Form mit axialer Stellung der Substituenten an C-1 und C-5, die der alternativen 1C(D)-Konformation der D-Reihe entspricht.
Monosaccharides Containing Nitrogen in the Ring, XXIX. Synthesis and Conformational Analysis of -5(Benzyloxycarbonylamino)-5.6-dideoxy-β-L-idopyranose
-5(benzyloxycarbonylamino)-5.6-dideoxy-β-L-idose represents an equilibrium mixture of furanose 4 and piperidine form 5 with a relative amount of 1 : 4. According to n.m.r. data the piperidine sugars 6 and 7 largely prefer the Cl(L)-form with substituents at C-1 and C-5 in axial position, which corresponds to the alternative 1C(D) conformation in the D-series.
Patent•
03 Oct 1972
TL;DR: In this article, a process for the development of a pipe-drone is described, and a pipeline is proposed for the preparation of a pipelined mixture of the formulae.
Abstract: 1. A PROCESS FOR PRODUCING A PIPERIDINE COMPOUND OF THE FORMULA, 1-((R4,R5-PHENYL)-CO-CH2-CH2-CH2-),4-(R3,R1-PHENYL-), 4-R1-PIPERIDINE WHEREIN R1 IS HYDROXY, ALKYL HAVING UP TO 4 CARBON ATOMS, ALKOXY HAVING UP TO 4 CARBON ATOMS, ALKANOYL HAVING UP TO 5 CARBON ATOMS, ALKANOYLOXY HAVING UP TO 5 CARBON ATOMS, CARBOXY, ALKOXYCARBONYL HAVING UP TO 5 CARBON ATOMS CARBAMOYL, N-(C1-C3 ALKYL)CARBAMOYL, N-DI (C1-C3 ALKYL)CARBAMOYL, N-(C1-C4 ALKANOYL)AMINOMETHYL OR N-(C1-C4 ALKOXYCARBONYL)AMINOMETHYL; R2 AND R3 ARE RESPECTIVELY HYDROGEN, HYDROXY, ALKYL HAVING UP TO 4 CARBON ATOMS, ALKOXY HAVING UP TO 4 CARBON ATOMS, HALOGEN OR TRIFLUORIMETHYL; R4 IS HYDROGEN, HALOGEN, NITRO OR (C1-C4) ALKANOYLAINO AND R5 IS HALOGEN, WHICH COMPRISES DEGRADING A QUASTERNARY PIPERIDINIUM SALT OF THE FORMULA, 1-((R5,R4-PHENYL)-C(=Z)-CH2-CH2-CH2-),1-R,4-R1,4-(R2,R3- PHENYL-)-PIPERIDINIUM X(-) WHEREIN R IS BENZYL OR 2-PHENETHYL; X IS HALOGEN; Z IS OXYGEN OR ETHYLENEDIOXY; AND R1, R2, R3, R4 AND R5 ARE AS DEFINE ABOVE, AND IN CASE WHERE Z IS ETHYLENEDIOXY, HYDROLYZING THE RESULTING KETAL COMPOUND OF THE FORMULA, 1-((2-(R4,R5-PHENYL-)-1,3-DIOXOLAN-2-YL)-CH2-CH2-CH2-), 4-R1,4-(R2,R3-PHENYL-)-PIPERIDINE WHEREIN R1, R2, R3, R4 AND R5 ARE AS DEFINE ABOVE, TO REGENERATE THE CARBONYL FUNCTION.
TL;DR: In this article, 4-Nitrohomophthalic acid reacts with aromatic aldehydes in the presence of piperidine to yield 3-aryl-7-nitro-3,4-dihydroisocoumarins.
TL;DR: Pyrrolidine, morpholine, and piperidine react directly with the 20-oxo-17α, 21-dihydroxy-side-chain of corticosteroids to give 21-amino-derivatives, and n.m.r. data indicate the presence of an internal hydrogen bond between the 17α-hydroxy-group and the C-21 nitrogen atom.
Abstract: Pyrrolidine, morpholine, and piperidine react directly with the 20-oxo-17α, 21-dihydroxy-side-chain of corticosteroids to give 21-amino-derivatives. l.r. and n.m.r. data indicate the presence of an internal hydrogen bond between the 17α-hydroxy-group and the C-21 nitrogen atom. The reaction at the 4-en-3-one system leads, as expected, to 3-amino-3,5-dienes. Reactivity at C-3 follows the order pyrrolidine > morpholine > piperidine and can be explained on the basis of resonance theory and steric effects. It is possible to prepare either 21-amino-or 3,21-diamino-derivatives. An s-trans-structure is postulated for the 3,5-diene system; a cross-conjugated system is excluded on the basis of n.m.r. data. Corticosteroids without a 17α-hydroxy-group react at C-21 only, under more drastic conditions. A possible explanation of the function of the 17-hydroxy-group is advanced.
TL;DR: In this article, an asymmetrical internal perfluoroolefin reaction mechanism was discussed, where secondary amines such as diethylamine or piperidine were used to give a terminal enamine which was easily hydrolyzed to the corresponding amide.
Abstract: Perfluoro-4-methylpentene-2 [1] , an asymmetrical internal perfluoroolefin, reacted with secondary amines such as diethylamine or piperidine to give a terminal enamine [2], which was easily hydrolyzed to the corresponding amide [3]. The reaction mechanism was discussed.
TL;DR: The iminium salt, N,N-dimethyl-N-[2,6-diphenyl-4H-pyran-4-ylidene)ethylidene]iminium perolilorate (1), reacts with secondary amines, such as piperidine, by exchanging the dimethyl-amino function for a Piperidine as discussed by the authors.
TL;DR: In this paper, it was shown that trans-4-chloromethyl-5,5-dimethyl-2,7,8-trioxa-1-phosphabicyclo[3,2,1] octane and its 5-deuterio-derivative have a twist ring.
Abstract: 4,4-Dimethyl-2,7,8-trioxa-1-phosphabicyclo[3,2,1]octane and its 5-deuterio-derivative have been prepared and converted by chlorination followed by treatment with piperidine into trans-4-chloromethyl-5,5-dimethyl-2-oxo-2-piperidino-1,3,2-dioxaphosphorinan and its 4-deuterio-derivative. 1H N.m.r. data suggest that this piperidide and the intermediate monocyclic phosphorochloridate, as well as trans-5-chloromethyl-5-methyl-2-oxo-2-piperidino-1,3,2-dioxaphosphorinan, exist with the phosphorus-containing ring held in a rigid chair form. On the other hand the cis-stereoisomers of 4-chloromethyl-5,5-dimethyl-2-oxo-2-piperidino-(again demonstrated by use of the 4-deuterio-compound), 5-chloromethyl-5-methyl-2-oxo-2-piperidino-, and 2-chloro-5-chloro-methyl-5-methyl-2-oxo-1,3,2-dioxaphosphorinan probably possess a twist ring.
TL;DR: In this paper, a metal-halogen exchange between n-butyl-lithium and octachloro-4,4′-bipyridyl gave heptachloros 3lithio-4.4.6.
Abstract: Metal–halogen exchange between n-butyl-lithium and octachloro-4,4′-bipyridyl gave heptachloro-3-lithio-4,4′-bipyridyl, whereas nucleophilic substitution of the bipyridyl by piperidine took place at the 2- and 2′-positions. The reactions of the 3-lithio-compound with water, dimethyl sulphate, and aromatic nitriles gave the expected products. On heating in the presence of p-di-isopropylbenzene the 3-lithio-compound gave an adduct of 5,6-dichloro-4-(tetrachloro-4-pyridyl)-2-pyridyne.
TL;DR: In this paper, the degree of carbonium ionic character of the methylenic carbon atom attached to the nitroxy-group has been explained for N-Nitroxymethylpiperidine and N-nitroxymmethylsuccinimide.
Abstract: N-Nitroxymethylpiperidine and N-nitroxymethylsuccinimide have been prepared and their reactions with nucleophiles and nitric acid under various conditions have been compared. Their relative reactivities have been explained in terms of the degree of carbonium ionic character of the methylenic carbon atom attached to the nitroxy-group. 1,3-Dinitro-5-nitroxymethylperhydro-1,3,5-triazine has eluded preparation from either (a) the N-acetoxymethyl analogue with nitric acid in acetonitrile or (b) the N-chloromethyl analogue with silver nitrate also in acetonitrile. In case (a) an interaction with the solvent is explained and in case (b) the formation of the bicyclic nitramine 1,5-bis-(3,5-dinitroperhydro-1,3,5-triazin-1-yl)-2,4-dinitro-2,4-diazapentane has been proved.