ACYCLIC HYDROCARBONS
ACICLYC HYDROCARBONS
Features: alkynes are: hydrocarbons
-acyclic
-unsaturated ( NE = 2, due presents leg.π in connection component. Triple )
Nomenclature. Homologous series.
Giving obtain integer values of n homologous series in which the terms in any homologous series, 2 consecutive terms is differentiates between them by a methyl group. (-CH2-)
Name alkynes are formed by replacing suf - year of the corresponding alkane with suf-ina. Homologous series starts at n = 2
n
|
CnH2n-2
|
Alcan
|
CnH2n-2
|
Alchina
|
1
|
CH4
|
Metan
|
-
|
-
|
2
|
C2H6
|
Etan
|
C2H2
|
Etina (acetilena)
|
3
|
C3H8
|
Propan
|
C3H4
|
Propina
|
4
|
C4H10
|
butan
|
C4H6
|
butina
|
Isomerism in alkyne.
dinuclear-alkanes (spirit)
-cicloalchine
-diene
Alkynes, n = 4 presents the phenomenon of flavor. position that has given the possibility of triple bond. to occupy different positions in the chain
Butina shows the next two position isomers
C4H8: CH ≡ C-CH 2-CH 3 1 Butina
CH3-C ≡ C-CH 3 2 Butina
-1.54 Å in leg, C-C C ≡ C 1.21 Å
-1.33 Å in leg, C = C <180 ˚All due to hybridization and distance decreases from 1.1 in the case of CH-H Csp3 0.6 in Csp-H HC ≡ CH 0.6 ÅConsequently discrete sp hybridization at. of C is the polarization leg. C-H more pronounced than the other leg.Contact CSP - H = leg polar S-on and S + H. Csp Csp-H. This polarization of the bond gives acetylene, respectively alkynes with triple marginal connection weak acid character!
Getting alkynesI ENGINEERING
January. Methane: Cracking the arc-
-The incomplete combustion
February. As carbide (CARB) CaC2
2. ) Determination Additional alkynes by alkylation of metal acetylenes
I 1. Obtaining methane :
2CH4-> C2H2 +3 H2
Industrial transformation is done by two methods differ by the source of energy for reaction
It identifies:a process for the cracking of CH4 in the electric arcb incomlete combustion process
a) If this method provided the energy needed for decomposition reaction esste elements and occur between the two metal electrodes fed from a DC source. Besides the main reaction takes place and a number of side reactions and what their stopping place ptr sudden splashing of the reaction medium with cold water. There can still be avoided C reaction forming free
1500 ˚ C
CH4 -> C +2 H2
The method is applied to Borzesti
CH4 +1 / 2O2-> CO +2 H2
Acetylene carbon 2.Obtinerea Ca
As the ionic compound carbide = Ca 2 + and C-2 2 - ion C2 is made up of two atmospheres. The Chidrocarborizati sp joined by a triple leg. and that we find a negative charge each HC ≡ CHIn CaC2cele two positive charges of carbide ions were neutralized by Ca 2 +
Industrial CaC2 (carbide) is obtained by reduction to 2500 ˚ C with metallurgical coke Ca oxide obtained by thermal decomposition of limestone
800-1000 ˚ C
------------------- CaCO3> CaO + CO2
(Limestone)
2500 ˚ C
CaO + 3C ----------------> CaC2 + CO
(Carbide)
CaC2 is an ionic carbide (acetylene) to hydrolyze the metal release in normal conditions with acetylene. Reaction applies to both small-scale genre. Acetylene when oxyacetylene welding and industrial scale.
The reaction is violent and fast
CaC2 +2 H2O --------------> Ca (OH) 2 + C2H2
(Acetylene)
acetylene generator
Metals LaboratoryJanuary. Removal of hydrohalic of dihalo derivativesa vicinal:Transformation occurs in the presence of KOH / alc at a temperature of 100-150 ˚ C. In the first stage (I) derivative obtained hydrohalic elimination occurs. halog. That in the second (II) phase at higher temperature of 150 ˚ C to remove hydrohalic appropriate alkyne transformation.
Alc alc KOH KOH-HC-CH----------------->-C = CH------------>-C ≡ C-
XX 100-150 ˚ CX t> 150 ˚ C
- HX-HX
1,2-dichloroethane
Alc alc KOH KOH
CH2-CH2 ------------> CH = CH2 ------------------> HC ≡ CH
100-150 ˚ C Cl Cl Cl t> 150 ˚ C
- HCl-HCl
Alkenes not deshidrogeneaza the alkyne.
Alc alc KOH KOH-HC-CH----------------->-C = CH------------>-C ≡ C-
XX 100-150 ˚ CX t> 150 ˚ C
- HX-HX
1,2-dichloroethane
Alc alc KOH KOH
CH2-CH2 ------------> CH = CH2 ------------------> HC ≡ CH
100-150 ˚ C Cl Cl Cl t> 150 ˚ C
- HCl-HCl
Alkenes not deshidrogeneaza the alkyne.
The transformation of an alkene in alkyne is achieved through a sequence of
reactions such as:KOHalc> C = C <+ Br2 ------ >> C-C <------>-C = C <----->-C ≡ C------> CH2 = ------- CH2> CH ≡ CHBr Br
100 +50 ˚-HBrCH2 = CH2 2 Br ---> CH2-CH2 ------> CH = CH2 -----------> CH ≡ CH
HBr Br Br Br-t> 150 ˚ C
Alc alc KOH KOHCH3-CH = CH + Br2 -----------> CH3-CH-CH2 --------------> CH3-CH = CH2 ------ -----------> CH3-C ≡ CH
100-150 ˚ HBr Br Br-Br t> 150 ˚-HBr
CH2 = CH 2 C ≡ CH
----------->
Styrene Phenyl acetylene
Br Br
Br2 + CH = CH 2 C ≡ CH CH-CH2
Alc KOH
-----------> ----------->
-2HBr
b) Double dehydrogenation of a secondary germinal dehalogenat
The reaction takes place in the presence of KOH solution in stage Alcolica getting monohalides they correspond vinyl and stage IIA to the alkyne
x-Hx-HX-C-CH 2 ------------>-C = CH------------>-C ≡ C-
x KOH KOH alc alc x
Vacin dihalo derivatives are obtained from the reaction of a group in pentahalide crbonil P
x
! C = O, PX5 ----------> C
-Pox3 x
carbonyl gr. Carbonyl
reactions such as:KOHalc> C = C <+ Br2 ------ >> C-C <------>-C = C <----->-C ≡ C------> CH2 = ------- CH2> CH ≡ CHBr Br
100 +50 ˚-HBrCH2 = CH2 2 Br ---> CH2-CH2 ------> CH = CH2 -----------> CH ≡ CH
HBr Br Br Br-t> 150 ˚ C
Alc alc KOH KOHCH3-CH = CH + Br2 -----------> CH3-CH-CH2 --------------> CH3-CH = CH2 ------ -----------> CH3-C ≡ CH
100-150 ˚ HBr Br Br-Br t> 150 ˚-HBr
CH2 = CH 2 C ≡ CH
----------->
Styrene Phenyl acetylene
Br Br
Br2 + CH = CH 2 C ≡ CH CH-CH2
Alc KOH
-----------> ----------->
-2HBr
b) Double dehydrogenation of a secondary germinal dehalogenat
The reaction takes place in the presence of KOH solution in stage Alcolica getting monohalides they correspond vinyl and stage IIA to the alkyne
x-Hx-HX-C-CH 2 ------------>-C = CH------------>-C ≡ C-
x KOH KOH alc alc x
Vacin dihalo derivatives are obtained from the reaction of a group in pentahalide crbonil P
x
! C = O, PX5 ----------> C
-Pox3 x
carbonyl gr. Carbonyl
Thus the acetic alkyd can get acetylene
Cl Cl alc KOH
CH3-CH = O + 5e ----------> CH3-CH3 ----------> CH3-CH ----------> CH2 = CH- ---------> CH ≡ CH
POCl3 Cl-Cl-HClphosphorus oxychloride
CH3 CH3 Cl
C = O + 5e ---------> C -------------> CH = CH ---------> CH3-C ≡ CH
POCl3 CH3-CH3 CH3 Cl Cl-HCl
CH3-CH2C = O ---------> CH3-C ≡ C-CH3
CH3
CH3 CH3-CH2-CH2 Cl
C = A + --------- 5c> C ---------> CH3-CH = C-CH 3 ---------> CH3-C ≡ C-CH3
CH3 CH3 Cl Cl-HCl
February.
Cl Cl alc KOH
CH3-CH = O + 5e ----------> CH3-CH3 ----------> CH3-CH ----------> CH2 = CH- ---------> CH ≡ CH
POCl3 Cl-Cl-HClphosphorus oxychloride
CH3 CH3 Cl
C = O + 5e ---------> C -------------> CH = CH ---------> CH3-C ≡ CH
POCl3 CH3-CH3 CH3 Cl Cl-HCl
CH3-CH2C = O ---------> CH3-C ≡ C-CH3
CH3
CH3 CH3-CH2-CH2 Cl
C = A + --------- 5c> C ---------> CH3-CH = C-CH 3 ---------> CH3-C ≡ C-CH3
CH3 CH3 Cl Cl-HCl
February.
Obtaining higher alkynes by alkylation with halogenated conp (seeextensively composition acetylene subsection ionic substitution reactions at CSP) alkynes with triple marginal reaction with Na metal contact at 150 ˚ C by a substitution reaction of H Csp marginal acetylides getting a monoacid. This acetylene can react with a halogenated taking place subst. Na and the formation of a superior alkyne
150 ˚ C + + + HR-C ≡ CH + Na --------->-C ≡ C ---------->-C ≡ C ---------->-C ≡ CR
1/2H2-Nax
Thus the accetilena can be achieved by any alkyne triple monoalchinarea marginal edge and the alkyne triple dialchinare a boundless
100 ˚ C _ + + X-RCH ≡ CH + Na ---------> CH ≡ C Na --------->-CH ≡ CR
-1/2H2 Na-NaX + Imp ptr chain stretches, entered C
(200 ˚ C) -1/2H2
+ __ +
NAC NAC ≡
2 R'-X
--------> R'-C ≡ C-R 'Imp-2Nax because they get triple the middle
CH4 --------> CH ≡ C-CH3
1500 ˚ C + Na +-Cl CH3
2CH4 ---------> CH ≡ CH -------------------> --------- CNA ≡ CH> CH ≡ C -CH3
-150 ˚ C-1/2H2-3H2-NaCl
CH4 ---------> CH3-C ≡ C-CH3
1500 ˚ C Na + Na +2 Cl CH3-
2CH4 ---------> --------- CH ≡ CH> CH ≡ CNA ---------> ≡ NAC NAC ---------- > CH3-C ≡ C-CH
-3H2 1500 ˚ C-1/2H2 200 ˚ C-H2-H2-2NaCl
CH4 ---------> CH3-CH-C ≡ C-CH-CH3
Acetylene
1500 ˚ C + Na + Na2CH4 ---------> --------- CH ≡ CH> CH ≡ CNA ---------> NaCl ≡ CNA ---------> CH3-CH-Cl + + Cl-NAC NAC ≡ CH-CH3
3H2 150 ˚ C-CH3 CH3-NaCl
---------> CH3-CH-C ≡ C-CH-CH3
NaCl CH3-CH3
Physical Properties
Acetylene is a colorless gas with pleasant ethereal odor. Acetylene carbide comes from presenting a garlicky odor due to impurity carbide. It is soluble in water volume ratio 1: 1 (one of the few oil-soluble H2O). The property is due to the acetylene CH bond polarity. It is soluble in organic solvents (acetylene).
Can not compress under pressure in steel cylinders as an explosion occurs. Are used to prevent its special steel cylinders filled with a porous mass of asbestos or kisellgen which was impregnated with acetone. On 12 atm 300 l 1l dissolved acetylene acetylene.
CH3-C = C-CH 3 ---------> CH3-C ≡ CH
CH3 CH3
[A] CH3-CH3 CH3 CH3 tilt alc KOH-HClCH3-C = C-CH 3 ---------> C = O + O = C ---------> C ---------> CH2 = C-CH3 ---------> CH ≡ C-CH3
KHnO4 + H2SO4 CH3 CH3 CH3-CH3 + HCl Cl 5e
HClCH2 = CH-CH2-CH3 + HCl ---> CH3-CH-CH-CH2-CH3 ------> CH3-CH + CH-CH3 + Br2 ---------> CH3- CH-CH-CH3
Alc KOH Br Br
Alc KOH-HBr
---------> CH3 CH3 CH3 = C ---------> CH3-C ≡ C-CH3
t.150 ˚ C-HBr alc KOH
CH4 ---------> CH3-CH-C ≡ C-CH-CH3
CH3 CH3
T = 1500 ˚ C + Na + Na + _ + __ + 2 Cl-CH-CH3CH4 ---------> --------- CH ≡ CH> CH ≡ C Na ---------> Na Na ------- C ≡ C ---------> CH3-CH-C ≡ C-CH-CH3
-3H2 -1/2H2 200 ˚ C 200 ˚ C -1/2H2 2NaCl CH3-CH3
2,5-dimethyl-5-EXENA
Chemical Properties:
Triple bond of the alkyne component having two links п, alkynes unsaturated character will have a more pronounced than they alkenes.
The main reactions:
I addition of H2, X2, HX, H2O, CH3COOH, CH = CH-CN, HCN
II dimerization reaction
III cyclic trimerization reaction
IV oxidation reaction
V substitution at C sp
I hydrogenation reaction
Can be defined in two stages, the addition product with different degree of saturation according et. Addition:a) Total - molecular H2 in the presence of finely divided metals (Ni, Pt, Pd) => dividing triple bond in connection simple. As follows:
Ni Pt Pd-C ≡ C-2 H 2 ---------------->-CH2-CH2-alkyne alkane
Ni Pt PdCH ≡ CH +2 H2 ----------------> CH3-CH3Acetylene ethane
Ni Pt Pd-C ≡ CH 2 CH 3 H 2 ----------------> CH3-CH2-CH3
Propane
CH ≡ C-CH2-CH3 Ni Pt Pd
1-butene, 2 H 2 ----------------> CH3-CH2-CH2-CH3CH3-C-CH3 butane2-butene
b) part - is done in the corresponding alkene resulting homogeneous catalysis. The reaction is stereo specific reaction the catalyst riding. Thus the use of poisoned Pd catalyst salts Pb 2 +, H => cis isomer
1/2H2-Nax
Thus the accetilena can be achieved by any alkyne triple monoalchinarea marginal edge and the alkyne triple dialchinare a boundless
100 ˚ C _ + + X-RCH ≡ CH + Na ---------> CH ≡ C Na --------->-CH ≡ CR
-1/2H2 Na-NaX + Imp ptr chain stretches, entered C
(200 ˚ C) -1/2H2
+ __ +
NAC NAC ≡
2 R'-X
--------> R'-C ≡ C-R 'Imp-2Nax because they get triple the middle
CH4 --------> CH ≡ C-CH3
1500 ˚ C + Na +-Cl CH3
2CH4 ---------> CH ≡ CH -------------------> --------- CNA ≡ CH> CH ≡ C -CH3
-150 ˚ C-1/2H2-3H2-NaCl
CH4 ---------> CH3-C ≡ C-CH3
1500 ˚ C Na + Na +2 Cl CH3-
2CH4 ---------> --------- CH ≡ CH> CH ≡ CNA ---------> ≡ NAC NAC ---------- > CH3-C ≡ C-CH
-3H2 1500 ˚ C-1/2H2 200 ˚ C-H2-H2-2NaCl
CH4 ---------> CH3-CH-C ≡ C-CH-CH3
Acetylene
1500 ˚ C + Na + Na2CH4 ---------> --------- CH ≡ CH> CH ≡ CNA ---------> NaCl ≡ CNA ---------> CH3-CH-Cl + + Cl-NAC NAC ≡ CH-CH3
3H2 150 ˚ C-CH3 CH3-NaCl
---------> CH3-CH-C ≡ C-CH-CH3
NaCl CH3-CH3
Physical Properties
Acetylene is a colorless gas with pleasant ethereal odor. Acetylene carbide comes from presenting a garlicky odor due to impurity carbide. It is soluble in water volume ratio 1: 1 (one of the few oil-soluble H2O). The property is due to the acetylene CH bond polarity. It is soluble in organic solvents (acetylene).
Can not compress under pressure in steel cylinders as an explosion occurs. Are used to prevent its special steel cylinders filled with a porous mass of asbestos or kisellgen which was impregnated with acetone. On 12 atm 300 l 1l dissolved acetylene acetylene.
CH3-C = C-CH 3 ---------> CH3-C ≡ CH
CH3 CH3
[A] CH3-CH3 CH3 CH3 tilt alc KOH-HClCH3-C = C-CH 3 ---------> C = O + O = C ---------> C ---------> CH2 = C-CH3 ---------> CH ≡ C-CH3
KHnO4 + H2SO4 CH3 CH3 CH3-CH3 + HCl Cl 5e
HClCH2 = CH-CH2-CH3 + HCl ---> CH3-CH-CH-CH2-CH3 ------> CH3-CH + CH-CH3 + Br2 ---------> CH3- CH-CH-CH3
Alc KOH Br Br
Alc KOH-HBr
---------> CH3 CH3 CH3 = C ---------> CH3-C ≡ C-CH3
t.150 ˚ C-HBr alc KOH
CH4 ---------> CH3-CH-C ≡ C-CH-CH3
CH3 CH3
T = 1500 ˚ C + Na + Na + _ + __ + 2 Cl-CH-CH3CH4 ---------> --------- CH ≡ CH> CH ≡ C Na ---------> Na Na ------- C ≡ C ---------> CH3-CH-C ≡ C-CH-CH3
-3H2 -1/2H2 200 ˚ C 200 ˚ C -1/2H2 2NaCl CH3-CH3
2,5-dimethyl-5-EXENA
Chemical Properties:
Triple bond of the alkyne component having two links п, alkynes unsaturated character will have a more pronounced than they alkenes.
The main reactions:
I addition of H2, X2, HX, H2O, CH3COOH, CH = CH-CN, HCN
II dimerization reaction
III cyclic trimerization reaction
IV oxidation reaction
V substitution at C sp
I hydrogenation reaction
Can be defined in two stages, the addition product with different degree of saturation according et. Addition:a) Total - molecular H2 in the presence of finely divided metals (Ni, Pt, Pd) => dividing triple bond in connection simple. As follows:
Ni Pt Pd-C ≡ C-2 H 2 ---------------->-CH2-CH2-alkyne alkane
Ni Pt PdCH ≡ CH +2 H2 ----------------> CH3-CH3Acetylene ethane
Ni Pt Pd-C ≡ CH 2 CH 3 H 2 ----------------> CH3-CH2-CH3
Propane
CH ≡ C-CH2-CH3 Ni Pt Pd
1-butene, 2 H 2 ----------------> CH3-CH2-CH2-CH3CH3-C-CH3 butane2-butene
b) part - is done in the corresponding alkene resulting homogeneous catalysis. The reaction is stereo specific reaction the catalyst riding. Thus the use of poisoned Pd catalyst salts Pb 2 +, H => cis isomer
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