15031-77-3Relevant academic research and scientific papers
Proton NMR and IR study of self-association in pyridylalkanols: Open or cyclic dimers? Higher polymers?
Lomas, John S.,Adenier, Alain,Cordier, Christine
, p. 295 - 307 (2006)
1H NMR measurements indicate that (X-pyridyl)alkanols of the general formula (C5H4N)(CH2)nOH, where n = 1, 2 or 3, self-associate as open dimers, cyclic dimers, trimers and tetramers, with considerable variations depending on the position of the alkyl chain and its length. (X-Pyridyl)propan-2-ols behave like the corresponding pyridylmethanols with, however, somewhat lower association constants. The IR spectra of 3-(X-pyridyl)-2,2,4,4-tetramethylpentan-3-ols (X = 3 or 4) in carbon tetrachloride suggest weak association, while the 2-pyridyl derivative occurs mainly as the intramolecularly hydrogen-bonded rotamer. The OH NMR shifts for the 3- and 4-pyridyl derivatives in benzene are concentration-dependent, but neither the equilibrium constants nor the degree of association can be evaluated. Benzyl alcohol in benzene associates as an open dimer and a cyclic tetramer, as does 2phenylpropan-2-ol, only more weakly. Rotation barriers for 3-(X-pyridyl)-2,2,4,4-tetramethylpentan-3-ols (X = 2, 3 or 4) in DMSO or nitrobenzene are 20-21 kcal mol-1. Copyright
The photochemistry of metyrapone in the solid state
Fasani, Elisa,Mella, Mariella,Albini, Angelo
, p. 394 - 396 (1997)
Metyrapone (2-methyl-1,2-di-3-pyridyl-1-propanone) undergoes α-cleavage upon irradiation in the solid state. The reaction occurs at the crystal surface, and the radicals formed in part recombine to give dipyridylketones, and in part add oxygen to give nicotinic acid and 3-(1- hydroxymethylethyl)pyridine. The crystals partially melt and the reaction continues until complete decomposition of the starting material.
Access to "friedel-Crafts-Restricted" tert -alkyl aromatics by activation/methylation of tertiary benzylic alcohols
Hartsel, Joshua A.,Craft, Derek T.,Chen, Qiao-Hong,Ma, Ming,Carlier, Paul R.
experimental part, p. 3127 - 3133 (2012/05/20)
Herein we describe a two-step protocol to prepare m-tert-alkylbenzenes. The appropriate tertiary benzylic alcohols are activated with SOCl2 or concentrated HCl and then treated with trimethylaluminum, affording the desired products in 68-97% yields (22 examples). This reaction sequence is successful in the presence of a variety of functional groups, including acid-sensitive and Lewis-basic groups. In addition to t-Bu groups, 1,1-dimethylpropyl and 1-ethyl-1-methylpropyl groups can also be installed using this method.
Highly alkyl-selective addition to ketones with magnesium ate complexes derived from Gignard reagents
Hatano, Manabu,Matsumura, Tokihiko,Ishihara, Kazuaki
, p. 573 - 576 (2007/10/03)
(Chemical Equation Presented) A highly efficient alkyl-selective addition to ketones with magnesium ate complexes derived from Grignard reagents and alkyllithiums is described. The nucleophilicity of R in R3MgLi is remarkably increased compared to that of the original RLi or RMgX, while the basicity of R3MgLi is decreased. Furthermore, a highly R-selective addition to ketones is demonstrated using RMe2MgLi in place of R 3MgLi.
Tert-butyldiphenylsilylmethyl triflate: Preparation and dipolar cycloaddition reactions of 1-(tert-butyldiphenylsilylmethyl)-6-cyano-4-methyl-1,2,5,6-tetrah ydropyridine
Hart, David J.,Huang, Ying
, p. 3203 - 3213 (2007/10/03)
Alkylation of substituted pyridines with tert-butyldiphenylsilylmethyl triflate provides N-[tert-butyldiphenylsilylmethyl]pyridinium triflates in excellent yields. Reductive cyanation of the pyridinium triflates provides 1-(tert-butyldiphenylsilylmethyl)-6-cyano-1,2,5,6-tetrahydropyrid ines, azomethine ylid precursors, in modest yields. An unexpected dipolar cycloaddition reaction of an ylid derived from the title 6-cyanopiperidine is described.
Pyridyl-propan-2-yl esters of 1-adamantane carboxylates
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, (2008/06/13)
Compounds having the general formula: STR1 wherein each of R 1 and R 2 independently represents hydrogen or alkyl of 1 to 4 carbon atoms;A represents --O-- or --CR 4 R 5, where R 4 and R 5 are defined as for R 1 or R 2 ;R 3 represents an adamantyl group; andPy represents a 3- or 4-pyridyl group, as free bases or their pharmaceutically acceptable salts are useful in treating androgen-dependent, especially prostatic, cancer.
The photochemistry of metyrapone
Fasani, Elisa,Mella, Mariella,Monti, Sandra,Sortino, Salvatore,Albini, Angelo
, p. 1889 - 1894 (2007/10/03)
Metyrapone undergoes efficient α-cleavage via the n0?* triplet.The fate of the resulting acyl and alkyl radicals has been determined by transient studies as well as through the isolation of the final products, quantum yield measurements and trapping studies.Processes previously documented for carbocyclic analogues of 1, such as disproportionation and coupling of the alkyl radicals and recombination to the starting compound are here accompanied by another major process, viz. coupling with attack of the acyl radical on the pyridine ring, which eventually leads mainly to a polymeric material.
3- and 4-pyridylalkyl adamantanecarboxylates: Inhibitors of human cytochrome P450(17α) (17α-hydroxylase/C17,20-lyase). Potential nonsteroidal agents for the treatment of prostatic cancer
Chan, Ferdinand C. Y.,Potter, Gerard A.,Barrie, S. Elaine,Haynes, Benjamin P.,Rowlands, Martin G.,Houghton, John,Jarman, Michael
, p. 3319 - 3323 (2007/10/03)
Various 3- and 4-pyridylalkyl 1-adamantanecarboxylates have been synthesized and tested for inhibitory activity toward the 17α-hydroxylase and C17,20-lyase activities of human testicular cytochrome P450(17α). The 4-pyridylalkyl esters were much more inhibitory than their 3- pyridylalkyl counterparts. The most potent was (S)-1-(4-pyridyl)ethyl 1- adamantanecarboxylate (3b; IC50 for lyase, 1.8 nM), whereas the (R)- enantiomer 3a was much less inhibitory (IC50 74 nM). Nearly as potent as 3b was the dimethylated counterpart, the 2-(4-pyridylpropan-2-yl) ester 5 (IC50 2.7 nM), which was also more resistant to degradation by esterases. In contrast to their 4-pyridyl analogs, the enantiomers of the 1-(3- pyridyl)ethyl ester were similarly inhibitory (IC50 for lyase; (R)-isomer 8a 150 nM, (S)-isomer 8b 230 nM). Amides corresponding to the 4- pyridylmethyl ester 1 and the (S)-1-(4-pyridyl)ethyl ester 3b, respectively 11 and 15b, were much less inhibitory than their ester counterparts. On the basis of a combination of inhibitory potency and resistance to esterases, the ester 5 was the best candidate for further development as a potential nonsteroidal inhibitor of cytochrome P450(17α) for the treatment of prostate cancer.
Organomolybdenum and Organotungsten Reagents, V. - On the Additive, Reductive Carbonyl Dimerization (ARCD Reaction)
Kauffmann, Thomas,Jordan, Jan,Voss, Karl-Uwe,Wilde, Heinz-Wilhelm
, p. 2083 - 2092 (2007/10/02)
Reagents of the type R4(PrO)4(μ-PrO)2W2 (3; R = Me, Et, Pr, Bu, sBu, iBu, Hex, Me3SiCH2, Ph) prepared in situ by the action of organolithium or Grignard compounds on (PrO)4(μ-PrO)2W2Cl4 (2), react with aromatic aldehydes or ketones and with the α,β-unsaturated ketone benzylidene acetone in a novel reaction, called the ARCD reaction, to give products 4 of the type RR'R''C-CRR'R'' with mostly good yields.In the case of benzylidene acetone and furfural besides the ARCD products the rearranged products 27 and 29 are formed.With the reagent Ph4(PrO)4(μ-PrO)2W2 (3b) ARCD reactions are also possible in moderate yields with aliphatic aldehydes and ketones.The more closely investigated reagent Me4(PrO)4(μ-PrO)2W2 (3a; decomposition at about -45 deg C) tolerates the aromatic bound functional groups Cl, F, OH, OMe, and NMe2 in the substrates, but not the NO2 and CO2Et substituents.It reacts with PhCOX (X = OEt, Cl, OCOPh) via acetophenone to give PhCMe2-CMe2Ph. - For the ARCD reactions a radical mechanism (Scheme 7) is postulated. - Key Words: Tungsten complexes/ Carbonyl dimerization
