4-Hydroxyethyl piperidine

Hydroxyethyl piperidine Phenthiazine-2-sulfonic acid dimethylamide... 

Perhydro derivatives of pyrido[l,2-7)][l,2]oxazines are frequently applied in the total synthesis of various alkaloids to control the stereochemistry, and pyrido[l,2-c][l,3]oxazines and [l,3]oxazino[3,4-u]quinolines were also used in the stereoselective syntheses of different alkaloids. Perhydropyrido[l,2-c][l,3]oxazines and their benzologs are formed form 2-(2-hydroxyethyl) piperidines and from their benzologs to justify the stereochemistry of 2-(2-hydroxyethyl) derivatives. Different optically active pipecolic acids can be prepared via 4-phenylperhydropyrido[2,l-c][l,4]oxazin-l-ones. 

Perhydropyrido[l,2-c][l,3]oxazin-l-one (115) was obtained, when l-terc-butoxycarbonyl-2-(2-hydroxyethyl)piperidine (114) was treated with CBr4 in the presence of PPh3 (99BMCL2621). Mesilate of 114 also afforded 115 on standing. 

QHi NjO 103-76-4) see Acetophenazine Carfenazine Clopenthixol Flupentixol Manidipine Opipramol Penimepicycline Perphenazine Tiaramide l-(2-hydroxyethyl)piperidine (C7H15NO 3040-44-6) see Flavoxate 4-(2-hydroxyethyl)piperidine... 

In the case of 2-(2-hydroxyethyl)piperidine it is not necessary to protect the NH group because of steric hindrance at this position. The imino function within the pyridinoindole is not nucleophilic enough to react with CDI. 

Figure 19. Correlations in the HSQC-1,1-ADEQUATE spectrum allow the overlapped resonances of the 2-(p-hydroxyethyl)piperidine moiety incorporated in the structure to be assigned (Figures 20 and 21). There are, however, resonance overlaps that complicate the F1SQC-1,1-ADEQUATE spectrum by virtue of artefact responses contained in the spectrum that are enclosed in boxes in Figure 21. Given the considerable overlap in the proton spectrum, the presence of artefact responses in the GIC processed HSQC-1,1-ADEQUATE spectrum is not surprising. It is also somewhat uncertain whether or not the 1,1-ADEQUATE spectrum itself would be tractable because of the proton resonance overlaps.

In one example of this type of cyclization aminoalcohol, 288, which was obtained by conjugate addition of racemic 2-(2-hydroxyethyl)piperidine to allyl phenyl sulfone, was converted into the corresponding chloride and cyclized in the presence of LDA to give 289 as a single diastereomer (Scheme 63) <2003JOC9389>. In a related approach, the primary alcohol group was activated for a similar cyclization by transformation into a mesylate <20010L2957>. 

Treatment of 3-phenylperhydropyrido[ 1,2-/ 1,3 oxazin-l -one with LAH gave a 1 9.5 mixture of 3-phenylphenylper-hydropyrido[l,2-c][l,3]oxazine and l-methyl-2-(2-phenyl-2-hydroxyethyl)piperidine <20050BC520>. Reduction of ds- >,4a- I-/ra .v-8-H-3-incthyl-8-pentyIperhydropyrido[ 1 1,3 oxazin-6-onc with NaBH4 at room temperature... 

V-(2-Hydroxyethyl)ethyleneimine, a311 A -(2-Hydroxyethyl)piperidine, pi82 2-(2-Hydroxyethyl)piperidine, p 183... 

Quinuclidone can be reduced to quinuclidine.6 Depending on the availability of starting materials, either this reduction or the dehydrative cyclization of 4-(2-hydroxyethyl)piperidine 10 is the most convenient synthesis of quinuclidine. 

Dealkylation of tertiary amines with dibenzoyl peroxide, 44, 74 Decarboxylation, intermolecular, of isocyanates to carbodiimides, 43,32 Decker synthesis of amines, 44, 7t, 75 Dehalogenation of l,l,2-trichloro-2,3,3-trifluorocydobutane, 42,45 Dehydration, of formamides with phosphorus oxychloride to isocy-anides, 41, 13, 101 of 4- 2-hydroxyethyl)piperidine to quinuclidine, 44, 90 Dehydrohalogenation of 2-chloroallyl-amines to propargylamines, 44,55 Delepine reaction, to prepare 2-bromo-allylamine, 43, 6 Deoxyanisoin, 40,16 Deoxybenzoin, 40, IT Deoxypiperoin, 40, IT Deaylamine, 41, 8T... 

Treatment of 6-methylperhydropyrido[2,l-h][l,4]oxazin-l-one with lithium aluminum hydride (LAH) in Et20 gave the ring-opened l-(2-hydroxyethyl)-2-hydroxymethyl-6-methylpiperidine (66JMC311 68USP 3388128). 2-Hydroxymethyl-l-(2-aryl-2-hydroxyethyl)piperidines were obtained from 3-aryl-3-hydroxyperhydropyrido[2,l-h][l,4]oxazines by catalytic reduction over Pd-C or Pd(OH)2-C, or by treatment with NaBH4... 

H2-labelled thioridazine 56 (the phenothiazine-type antipsychotic agent) has been obtained recently39 for metabolic and pharmacokinetic studies by a new route (equation 16) from 2-(2-hydroxyethyl)piperidine 57. The key steps in this sequence of reactions involve ruthenium tetroxide oxidation of the 7V,0-diacetylated starting material 58 and subsequent lithium aluminium deuteride reduction of the 2-(2-acetoxyethyl)-6-piper-idinone (59, R = Ac). Treatment of 60 with thionyl chloride produced 2-(2-chloroethyl)-l-methyl[6,6-2H2]piperidine which, on N(10)-alkylation of 2-methylthio-10i/-phenothia-zine, yielded 56. For each of the seven steps in the conversion of 57 to 56 the yield has been at least 76%40. 

The acetyl derivative (30) may be converted by Wolff-Kishner reduction into l,4-dimethyl-3-ethyl-3-piperideine (31).26 The latter compound is obtained in 17% yield also by dehydration of 1,4-dimethyl-3-( l-hydroxyethyl)piperidine (32) by the xanthate method.28 On the other hand, dehydration of the carbinol (32) with phosphorus pentoxide in toluene or by heating in concentrated hydrochloric aoid gives a mixture of isomeric l,4-dimethyl-3-ethylidenepiperidines (33a, b).28... 

To our knowledge, one alternative route to simple enantiopure quinuclidine-2-carboxylic acid has recently been described by Corey who assembled target molecule 68 whereas racemic 68 was first synthesized several decades ago by Prelog and [44]. Parent quinuclidine-2-carboxylic acid ester 68 that is structurally related to proline and pipecolinic acid was obtained from commercial 4-(2-hydroxyethyl)-piperidine in six chemical steps including one tartaric acid-mediated resolution (Scheme 12.17) [45]. A cyanoactivated intramolecular SN2 reaction delivered the strained [2.2.2]bicyclic system. The cyano group serves as a handle of further functionality and elaboration. 

R)-2-[1S,3S,5S)-3,5-DIMETHYL-2-OXOCYCLOHEXYL)l-2-HYDROXYETHYL]PIPERIDINE-2,6-OIONE 4-(2- 3,5-DIMETHYL-2-OXOCYCLOHEXYL)-2-HYDROXYETHYL-, (1 S-(1, ALPHA,(S ) 4-<2- 3,5-DlMETHYL-2-OXOCYCLOHEXYL).2-HYDROXYETHYL-, (1S- 1 ALPHA (S ), 3 ALPHA,S-BETA))-2,6-PIPERIDINEDIONE... 

Hydrogenation of this group of pyridines requires little comment. A number of catalysts were employed under a variety of conditions. Ruthenium dioxide is favored in this laboratory in the reduction of these compounds because of the speed of reaction and the absence of side products. 2-(2-Hydroxyethyl)piperidine has been obtained in excellent yield after the hydrogenation of the corresponding pyridine (5). In contrast, a reaction in the presence of Raney nickel at 150° and 130 atm gave less than 50% of reduction product plus di-[2-(2-piperidyl)-ethyl] ether (87). 4-(2-Hydroxyethyl)pyridine has been converted to the piperidine by means of ruthenium catalyst (86a). Brown and Eldred reported that there was no hydrogen uptake using nickel catalysts at 200° and 200 atm (87a). 

Dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-l-piperidine ethanol. See Dimethylsuccinate/tetramethyl hydroxy-1-hydroxyethyl piperidine polymer Dimethylsuccinate/tetramethyl hydroxy-1-hydroxyethyl piperidine polymer CAS 65447-77-0... 

Tinuvin 234. See 2-[2-Hydroxy-3,5-di-(1,1-dimethylbenzyl) phenyl]-2H-benzotriazole Tinuvin 326. See Bumetrizole Tinuvin 327. See 2-(3, 5 -Di-t-butyl-2 -hydroxyphenyl)-5-chlorobenzotriazole Tinuvin 328. See 2-(2 -Hydroxy-3,5 -di-t-amylphenyl) benzotriazole Tinuvin 329. See Octrizole Tinuvin 571. See Phenol, 2-(2H-benzotriazole-2-yl)-4-methyl-6-dodecyl Tinuvin 622, Tinuvin 622LD. See Dimethylsuccinate/tetramethyl hydroxy-1 -hydroxyethyl piperidine polymer Tinuvin 765. See Bis (1,2,2,6,6-pentamethyl-4-pipehdinyl) sebacate... 

Copper iodide (ous) p-Cresol/dicyclopentadiene butylated reaction product 2,6-Di-t-butyl-4-ethyl phenol 3,5-Di-t-butyl-4-hydroxyhydrocinnamic acid, 1,3,5-tris (2-hydroxyethyl)-s-triazine-2,4,6-(1H,3H,5H)-trione triester 2,4-Di-t-butylphenyl 3,5-di-t-butyl-4-hydroxybenzoate Dicetyl thiodipropionate Dicyandiamide Didodecyl-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxylate Dimethylsuccinate/tetramethyl hydroxy-1 -hydroxyethyl piperidine polymer Dimyristyl thiodipropionate... 

Barium stearate Benzophenone-12 Cadmium laurate Dimethylsuccinate/tetramethyl hydroxy-1-hydroxyethyl piperidine polymer N-( p-Ethoxycarbony I phenyl )-N -ethy l-N -phenylformamidine 2-(2 -Hydroxy-3,5 -di-t-amylphenyl) benzotriazole 4,4 -lsopropylidenediphenol alkyl (Cl2-15) phosphites Lead carbonate Lead carbonate basic Lead phthalate, dibasic Zinc stearate... 

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