6221-74-5Relevant academic research and scientific papers
Ammonium Adduct Ion in Ammonia Chemical Ionization Mass Spectrometry. 2 - Mechanism of Elimination of Neutrals from the Ammonium Adduct Ion
Nakata, Hisao,Hoshino, Yoshihiko,Takeda, Naohito,Tatematsu, Akira
, p. 467 - 470 (1985)
The mechanism of elimination of ROH (R = H or CH3) from the ammonium adduct ion, +, of 1-adamantanol and its methyl ether is examined by using linked-scan metastable ion spectra and by measuring the dependence of the peak intensity ratio +/+ on ammonia pressure.For 1-adamantanol both SNi and SN1 reactions are suggested in metastable ion decomposition, while only the SN1 mechanism is operative in the ion source.For 1-adamantanol methyl ether the SN1 reaction predominates both in metastable ion decomposition and in the ion source reaction.
Solvent-equilibrated homoadamantyl chloride ion pairs from chloroformate or oxachlorocarbene fragmentations
Moss, Robert A.,Tian, Jingzhi,Sauers, Ronald R.
, p. 4293 - 4296 (2004)
(Chemical Equation Presented) Fragmentations of 3-homoadamantyl chloroformate and 3-homoadamantyloxychlorocarbene produce identical ion pairs as product-determining intermediates.
THE IMPORTANCE OF STERIC BULK AND ACIDITY IN SOLVOLYSIS. THE MECHANISM OF SOLVOLYSIS OF 1-ADAMANTYL BROMIDE
McManus, Samuel P.,Zutaut, Steven E.
, p. 2859 - 2862 (1984)
Product selectivities from solvolysis of 1-adamantyl bromide in several binary protic solvents are revealing about the relative importance of solvent acidity and bulk.
Exhaustive One-Step Bridgehead Methylation of Adamantane Derivatives with Tetramethylsilane
Bonsir, Maxime,Davila, Christian,Geerts, Yves,Kennedy, Alan R.
supporting information, p. 5227 - 5237 (2021/10/19)
A methylation protocol of adamantane derivatives was investigated and optimized using AlCl3 and tetramethylsilane as the methylation agent. Substrates underwent exhaustive methylation of all available bridgehead positions with yields ranging from 62 to 86 %, and up to six methyl groups introduced in one step. Scaling-up of the reaction was demonstrated by performing the >40 gram-scale synthesis of 1,3,5,7-tetramethyladamantane with 62 % yield. For several substrates, rearrangements were observed, as well as cleavage of functional groups or Csp3?Csp2 bonds or even cyclohexyl-adamantyl bonds. Based on mechanistic studies, it is suggested that a reactive methylation complex is formed from tetramethylsilane and AlCl3. X-ray diffraction structures of hexamethylated bis-adamantyls reveal elongation or widening of sp3 carbon bonds between adamantyl moieties to 1.585(3) ? and 125.26(9)° due to repulsive H???H contacts.
Synthesis of Trialkylamines with Extreme Steric Hindrance and Their Decay by a Hofmann-like Elimination Reaction
Banert, Klaus,Hagedorn, Manfred,Heck, Manuel,Hertel, Raphael,Ihle, Andreas,Müller, Ioana,Pester, Tom,Shoker, Tharallah,Rablen, Paul R.
, p. 13630 - 13643 (2020/11/13)
A number of amines with three bulky alkyl groups at the nitrogen, which surpass the steric crowding of triisopropylamine considerably, were prepared by using different synthetic methods. It turned out that treatment of N-chlorodialkylamines with organometallic compounds, for example, Grignard reagents, in the presence of a major excess of tetramethylenediamine offered the most effective access to the target compounds. The limits of this method were also tested. The trialkylamines underwent a dealkylation reaction, depending on the degree of steric stress, even at ambient temperature. Because olefins were formed in this transformation, it showed some similarity with the Hofmann elimination. However, the thermal decay of sterically overcrowded tertiary amines was not promoted by bases. Instead, this reaction was strongly accelerated by protic conditions and even by trace amounts of water. Reaction mechanisms, which were analyzed with the help of quantum chemical calculations, are suggested to explain the experimental results.
Nucleophilic Substitution of Aliphatic Fluorides via Pseudohalide Intermediates
Jaiswal, Amit K.,Prasad, Pragati K.,Young, Rowan D.
, p. 6290 - 6294 (2019/04/26)
A method for aliphatic fluoride functionalization with a variety of nucleophiles has been reported. Carbon–fluoride bond cleavage is thermodynamically driven by the use of silylated pseudohalides TMS-OMs or TMS-NTf2, resulting in the formation of TMS-F and a trapped aliphatic pseudohalide intermediate. The rate of fluoride/pseudohalide exchange and the stability of this intermediate are such that little rearrangement is observed for terminal fluoride positions in linear aliphatic fluorides. The ability to convert organofluoride positions into pseudohalide groups allows facile nucleophilic attack by a wide range of nucleophiles. The late introduction of the nucleophiles also allows for a wide range of functional-group tolerance in the coupling partners. Selective alkyl fluoride mesylation is observed in the presence of other alkyl halides, allowing for orthogonal synthetic strategies.
Synthesis of 1-, 2-Methoxy-, 1,3-Dimethoxyadamantanes And 1-, 4-Methoxydiadamantanes by Reaction of Adamantyl and Diadamantyl Halides with Dimethyl Carbonate in the Presence of Zeolite Catalysts
Khusnutdinov,Shchadneva,Mayakova, Yu. Yu.
, p. 1728 - 1730 (2019/02/12)
1-, 2-Methoxy-, 1,3-dimethoxyadamantane, and 1-, 4-methoxydiadamantane were prepared by the reaction of adamantyl and diadamantyl halides with dimethyl carbonate in the presence of zeolite catalysts NiHY or FeHY free of binders. Optimum ratio of catalysts and reagents were found and the reaction conditions for the selective synthesis of methoxyadamantanoids were developed.
Alkylation of dicarbonyl compounds with 1-bromoadamantane in the presence of metal complex catalysts
Khusnutdinov,Shchadneva,Khisamova
, p. 329 - 331 (2016/06/06)
Adamantyl-substituted dicarbonyl compounds have been synthesized by reactions of 1-bromo-adamantane with ethyl acetoacetate, 1,3-diphenylpropane-1,3-dione, and dimethyl malonate in the presence of iron and manganese complexes.
Synthesis of 1-adamantyl alkyl ethers by intermolecular dehydration of 1-adamantanol with alcohols catalyzed by copper compounds
Khusnutdinov, Ravil I.,Bayguzina, Alfiya R.,Mukminov, Rinat R.,Gimaletdinova, Leisan I.,Dzhemilev, Usein M.
, p. 342 - 349 (2014/07/07)
Adamantyl alkyl ethers were synthesized in high yields by intermolecular dehydration of 1-adamantanol with alcohols in the presence of copper-containing catalysts.
Synthesis of alkyl methyl ethers and alkyl methyl carbonates by reaction of alcohols with dimethyl carbonate in the presence of tungsten and cobalt complexes
Khusnutdinov,Shchadneva,Mayakova
, p. 790 - 795 (2014/08/18)
Alkyl methyl ethers and alkyl methyl carbonates were synthesized by reaction of alcohols with dimethyl carbonate in the presence of tungsten and cobalt carbonyls. Optimal reactant and catalyst ratios, as well as reaction conditions, were found for selective formation of alkyl methyl ethers or alkyl methyl carbonates.
