Alkylation of cyclododecanone with α,ω-dibromoalkanes under conditions of phase-transfer catalysis

Alkylation of cyclododecanone with ,-dibromoalkanes Br(CH) _n Br (n=3, 4, 5) under conditions of phase-transfer catalysis in the presence of KOH results in the formation of either bicyclic ketones forn=3 and 5 or a mixture of bicyclic and spirocyclic ketones forn=4.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1436–1438, August, 1994.     

A simple synthesis for 2-acetonylcyclododecanone

A simple method is proposed for the alkylation of cyclododecanone by propargyl halides under phase transfer catalysis conditions with the formation of 2-propargylcyclododecanone. The hydration of 2-propargylcyclododecanone upon catalysis by mercury compounds leads to either 14-methyl-13-oxabicyclo[10.3.0]-pentadeca-1(12),14-diene or 2-acetonylcyclododecanone depending on the reaction conditions. Both these compounds are also readily obtained from 2-(2-chloropropen-2-yl)cyclododecanone which readily forms upon the alkylation of cyclododecanone by 1,2-dichloropropene under phase transfer catalysis conditions.Translated from Izvestiya Akademil Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 963–965, April, 1991.     

Mesh adaptation based on functional a posteriori estimates with Raviart-Thomas approximation

Adaptive algorithms based on functional a posteriori estimates for the Dirichlet problem for the stationary diffusion equation with jump discontinuities in the equation coefficients are compared. The algorithms have been implemented in MATLAB with the use of both standard finite element approximations and the zero-order Raviart-Thomas approximation. The adaptation results are analyzed using indicators of the local error distribution. Specifically, sequences of finite-element partitions, effectivity indices of estimates, and relative errors of approximate solutions are compared.     

Preparation of brassylic acid from 5,6,7,8,9,10,11,12,13,14-decahydrocyclododeca[1,2-d]pyrimidine(1H, 3H)-2,4-dione obtained by the condensation of cyclododecanone and urea or biuret

A simple method is proposed for the preparation of brassylic acid by the alkaline hydrolysis of 5,6,7,8,9,10,11,12,13,14-decahydrocyclododeca[1,2-d]pyrimidine(1H, 3H)dione-2,4, which is the product of the condensation of cyclododecanone with urea or biuret. The condensation of the cyclododecanone with thiourea proceeds differently, leading to 5,6,7,8,9,10,11,12,13,14-decahydrocyclododeca[1,2-d]pyrimidine(1H, 3H)spirocyclododecane-2-thione-4.A. N. Nesmeyanov Institute of Organometallic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 226–229, January, 1992.     

Rearrangement of radicals during telomerization of ethylene with ethanol

Conclusions Rearrangement of the radicals, with a 1,5-migration of the hydrogen atom, occurs during the telomerization of ethylene with ethanol.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2593–2594, November, 1972.     

Functionalization of saturated hydrocarbons by aprotic superacids

The inefficient formylation of adamantane by CO initiated by superacid systems based on polyhalomethanes and aluminum halides becomes selective in the presence of methylcyclopentane and affords 1-adamantanecarbaldehyde in an almost quantitative yield under mild conditions.     

Oxidative transformations of cyclohexane,methylcyclopentane, and pentane on treatment with superelectrophiles based on polyhalomethane and aluminum halides

Cyclohexane and methylcyclopentane dimerize into dimethyldecalins on treatment with superelectrophilic systems containing polyhalomethanes (CBr₄, CCl₄, CHCl₃) and aluminum halides (AlBr₃, AlCl₃). At 20 °C, the yields of C₁₂H₂₂ hydrocarbons reach 140 mol.% based on the superelectrophile. Under the action of CBr₄·2AlBr₃ at 20 °C in CH₂Br₂ or without a solvent, n-pentane is converted predominantly into lower alkanes (mainly, isopentane). In addition, higher branched C₈--C₁₂ alkanes, small amounts of alkylated cyclohexanes, cycloalkenes, dienes, and alkylbenzenes are formed in a total yield of 20--23 % (w/w) based on pentane.