Pentane derivatives

Liquefied petroleum gas (LPG) Paraffin hydrocarbon gases comprising propane, butane, and pentanes derived from natural gas wells and from the petroleum refining process that remain as liquids when stored under pressure in tanks and bottles. 

For n = 1, this is the standard synthesis of [l.l.l]propellane 40a.20,21 Also for n = 3, this method makes [3.1.1]propellane 40c accessible with reasonable effort.22 Although [2.1.1]propellane 40b was detected by its IR spectrum at liquid nitrogen temperature,23 it could not be obtained as a stable compound via this route.22 The addition of halomethanes across the central bond by a radical chain mechanism is common to 40a and 40c. The addition of carbon tetrabromide to 40c afforded a 45% yield of 41.18 Likewise, a number of bicy-clo[l.l.l]pentane derivatives 42 were obtained by reaction of the corresponding halomethanes with 40a.17,24... 

A proposed mechanism of the bis(allene) cyclization involves the formation of the allyl(stannyl)palladium species 6, which undergoes carbocyclization to give vinyl(stannyl)palladium intermediate 7 (Scheme 36). Reductive elimination and cr-bond metathesis may lead to the formation of the m-pentane derivative and the bicyclic product, respectively. The cyclization of allenic aldehydes catalyzed by a palladium complex was also reported.163... 

The iV-TMS-A -chlorosilylethylenediamine (158) when heated cyclizes to 1,3,2-diazasilacyclo-pentane derivative (159) with elimination of Me3SiCl (Equation (7)) <92ZN(B)1377>. When the Si atom in the initial ethylenediamine is double bonded (160) the cyclization is accompanied by migration of MesSi from nitrogen to the double-bonded carbon atom (161) (Equation (8))... 

Problem 4.12 Name by the lUPAC system the isomers of pentane derived in Problem 4.2. ... 

Further transformations of l-iodobicyclo[l.l.l]pentane derivatives can be achieved by lithia-tion with rerf-butyllithium. transmctalation with zinc(II) chloride and palladium-catalyzed coupling with aryl iodides or aryl bromides using (dppf)FMCl2 as a catalyst.47... 

The solvolytic ring cleavage of the aminobicyclo[2.1.0]pentane derivative 15 with hydrogen iodide leads to the gcro-dimethylcyclopentene derivative 16 in 85% yield,54 Likewise, sulfuric acid converts 17 to 1855 and 19 to 20 in 96 and 41 % yield, respectively.56... 

TABLE 3. Calculated atomic distances (A) and angles (deg) of disilabicyclo[ 1.1.1 ]pentane derivatives.0... 

B-l. Which of the compounds shown is (are) correctly named as pentane derivatives, either as pentanals or pentanones ... 

The readily available methyl 3,3-dimethylcyclopropene-l-carboxylate (III/54) undergoes [2+2] cycloaddition with enamines e.g. the morpholine derivative III/55 to give 2-aminobicyclo[2.1.0]pentane derivatives, e.g. III/56. These compounds are transformed into cyclopentane derivatives, e.g. methyl 4-hydroxy-2,5,5-trimethyl-1-cyclopentenecarboxylate (III/57) by treatment with dilute mineral acids. 

The same effects were seen with mixed olefin feeds. The refinery stream described in Table III was blended with C.P. Grade Isobutane to obtain a 9.0-to-l.O Isobutane-to-olefln molar ratio. This feed was alkylated at temperatures ranging from to 45°C. The contact time was held constant at 1.0 minutes. The results are shown in Table IV. The alkylate compositions include pentanes derived from the feed, but only... 

Very recently, a stable 5-thiabicyclo[2.1.0]pentane derivative has been prepared by a thermal reaction. Co-evaporation of solutions of the partially fluorinated fullerene C60F18 and tetrathiafulvalene 109 in toluene led to 110 as the major product, which, on standing in toluene in the presence of CDCI3, reacted further to give the episulfide 111 (Scheme 58) <2003CEJ2008>. The formation of the initial product 110 was formulated via a unique six-electron process involving elimination of fluorine. The second reaction proceeds by elimination of the thioketene derivative 112. 

It is then a pentane derivative i.e.) 3-methyl pentane. The hexane boiling at 62°, viz., di-methyl propyl methane is 2-methyl pentane ... 

A number of 5-oxabicyclo[2.1.0]pentane derivatives have been prepared by several groups. Adam et al. obtained (21) from the endoperoxide precursor (20) with MCPBA as a single isomer (Scheme... 

Table 5. Bicyclo[2.1.0]pentane Derivatives via Addition of Dialkyl Azodicarboxylate or 4-Substituted-1,3,4-Triazole-3,5-dione to Cyclopentadienes...

Bicyclopentane reacted with acetic acid at 86 °C to give acetoxycyclopentane (27 a, 47%) and cyclopentene (29a, 53%). In the presence of /7-toluenesulfonic acid a substantial amount of tosyloxycyclopentane was isolated. Deuterio- and methyl-substituted bicyclo[2.1.0]pentane derivatives were submitted to acid-catalyzed and uncatalyzed acetolysis reactions. The distribution of products was analyzed and the rates of reaction calculated. It was shown that the acetolysis of the extremely strained bicyclopentane proceeds mainly via inversion of configuration at both ends of the central bond when it was cleaved. 5,5-Dimethylbicyclo[2.1.0]pentane (31) reacted via cleavage of one of the outside C —C bonds, leading to 1-cyclobutyl-1-methyl-ethyl products 33, rather than via cleavage of the central bond. ... 

Cyclopropene esters give aminobicyclo[2.1.0]pentane derivatives, which can undergo ring-opening reactions to cyclopentenes For example, methyl 3,3-dimethylcyclo-propene-l-carboxylate (37), obtained by photolysis of the corresponding pyrazolinic derivative, reacted with the diquinanic enamine 36 to give a mixture of the alkylation product 38 and the [2 + 2] cycloadduct 39 which, on acid treatment, was transformed into the triquinanic cyclopentene alcohol 40 (equation 6). 

For the isomerization of n-pentane, derive the rate expression if the surface reactit step of the dehydrogenation reaction were rate controlling. Contrast this with the corre rate of Problem 2.8, especially regarding variations with total pressure. 

Padwa, A., Shelter, E., Alexander, E. (1968). The correlation of the crystal and molecular structure with the nuclear magnetic resonance spectrum of a bicyclo[l.l.l]pentane derivative. J. Am. Chem. Soc., 90(14), 3717-3721. 

The name pentane derives from the Greek pente, meaning five, indicating that the molecule has five carbon atoms. The other names still use the term pentane, with a prefix iso or neo, trying to convey the fact that these are isomeric molecules. Naming the isomers can become cumbersome when the number of isomers increases. For this reason, chemists have created a standard naming system. ... 

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