Ngā Tauira Pātai e Matapaki ana i ngā Alkene me ngā Alkyne
Pendahuluan
I roto i te matū waro, ko ngā alkene me ngā alkyne he rōpū tino nui o ngā pūhui warowaihā. Ko ngā alkene he warowaihā kore-mākū kei roto i te kotahi, neke atu rānei ngā here takirua waro-waro (C=C), ko ngā alkyne ia he warowaihā kore-mākū kei roto i te kotahi, neke atu rānei ngā here takitoru waro-waro (C≡C). He mea nui te mārama ki ngā tauhohenga me ngā tikanga o ēnei momo pūhui e rua mō ngā momo tono i roto i te matū.
Ka tūhuratia e tēnei tuhinga ētahi tauira raruraru me ngā matapakinga e pā ana ki ngā alkene me ngā alkyne, hei āwhina i te mārama ki ngā ariā taketake me tō rātou whakamahinga i roto i ngā horopaki mahi.
Ngā Tauira Pātai me te Kōrero mō ngā Alkenes
Pātai 1:
Homai te ingoa IUPAC mō te matū e whai ake nei:
\[ \text{CH}_2=CH-\text{CH}_2-\text{CH}_3 \]
Kōrero:
1. Tāutuhia te mekameka roa rawa atu kei roto te hononga takirua. I tēnei wā, ko te mekameka roa rawa ko te butane (4 ngā waro).
2. Tauhia te mekameka mai i te pito e tata ana ki te hononga takirua.
3. Tāutuhia te tūranga o te hononga takirua. Kei waenganui i ngā waro 1 me te 2 te hononga takirua.
4. Ko te ingoa IUPAC o tēnei pūhui ko 1-butene.
Pātai 2:
Ka pāngia te pūhui 2-hexene e te tauhohenga tāpiri me te Br₂ i roto i te CCl₄. Tuhia te whārite tauhohenga, ka whakaingoa i te hua.
Kōrero:
1. Ko te tauhohenga tāpiri o te Br₂ ki ngā alkene ka puta he dibromoalkane.
2. Hanganga o te 2-hexene: CH₃-CH=CH-CH₂-CH₂-CH₃.
3. Mā te tāpiri i te Br₂ ki te hononga takirua ka puta te 2,3-dibromohexane:
\[ \kuputuhi{CH}_3-CH(\kuputuhi{Br})-CH(\kuputuhi{Br})-\kuputuhi{CH}_2-\kuputuhi{CH}_2-\kuputuhi{CH}_3 \]
Ngā Tauira Pātai me te Kōrero mō ngā Alkynes
Pātai 3:
Homai te ingoa IUPAC mō te matū e whai ake nei:
\[ \text{CH}_3-\text{C}≡\text{C}-\text{CH}_3 \]
Kōrero:
1. Tāutuhia te mekameka roa rawa atu kei roto he hononga takitoru. Ko te mekameka roa rawa he 4 waro.
2. Tauhia te mekameka mai i te pito e tata ana ki te hononga takitoru.
3. Tāutuhia te tūranga o te herenga takitoru. Kei waenganui i ngā waro 2 me te 3 te herenga takitoru.
4. Ko te ingoa IUPAC o tēnei pūhui ko 2-butyne.
Pātai 4:
Homai ngā mōhiotanga mō ngā hua i puta mai i te tauhohenga tāpiri o te HCl ki te 1-butyne.
Kōrero:
1. Hanganga o te 1-butyne: CH≡C-CH₂-CH₃.
2. Ko te tāpiritanga o te HCl ka hua ake i te tāpiritanga o te hononga takitoru me te hanganga o te hononga takirua, ka hua ake ko te 2-chlorobut-1-ene.
3. Mā te tāpiri atu i te HCl ki te hononga takirua ka puta te hua whakamutunga: 2,2-dichlorobutane.
Tikanga Tauhohenga
Pātai 5:
Whakamāramahia te tikanga o te tauhohenga hauwaihauora ā-alkene me te tauira tauhohenga: te propene me te HBr.
Kōrero:
1. Wāhanga 1: Te Whakapūngao
– Ka taunekeneke te here takirua o te propene (CH₂=CH-CH₃) me te proton (H⁺), ka hanga he warokātōtanga takawaenga.
– Ka tāpirihia e te H⁺ te maha o te waro, ka hua ake he kāpōnatanga pumau ake.
-Ka puta he kāpōna tuarua pumau i te wā e whakapūmua ana i te pūmua i C1.
2. Hipanga 2: Tāpiritanga Halide
– Ka whakaekea e te Bromide (Br⁻) te carbocation, ka puta ko te 2-bromopropane:
\[ \text{CH}_{3}-\text{CH}_{{\text{Br}}}-\text{CH}_2-\text{CH}_3 \]
Pātai 6:
Whakaahuahia, whakamāramahia hoki te tikanga o te tāpiritanga o te Br₂ ki te etune.
Kōrero:
1. Wāhanga 1: Te Hanganga o ngā Katote Pūroniuma
– Ka tauhohe a Ethyne (CH≡CH) ki a Br₂, mā te hanganga o tētahi katote bromonium takawaenga.
\[ \text{CH}\equiv\text{CH} + \text{Br}_2 \rightarrow \text{BrCH=CHBr} \]
2. Wāhanga 2: Te Hanganga o Dibromoalkyne
– Ka whakaekea tonutia ngā katote bromide kore utu (Br⁻) ki ngā katote bromonium hei hanga i ngā dibromoalkynes.
– Ko te tauhohenga bromination e whai ake nei ka puta he 1,1,2,2-tetrabromoethane mēnā ka mahia kia nui rawa.
Tauhohenga Whakahāora
Pātai 7:
Tāutuhia te hua ka puta mēnā ka whakahaerehia te tauhohenga ozonolysis ki runga i te 2-pentene.
2. Ka puta i te tauhohenga ozonolysis ngā kongakonga carbonyl e rua (ketone, aldehyde rānei).
3. Ka whakaozonolyzedhia te 2-pentene (CH₃-CH=CH-CH₂-CH₃) hei whakaputa i te butanone (CH₃-CO-CH₃) me te formaldehyde (H-COH).
Ngā Whakamahinga Hangahanga
Pātai 8:
Te hanga o te pūhui but-2-yne mai i te etanoru.
Kōrero
1. Tahurihia te etanoru (CH₃-CH₂OH) ki te etene (CH₂=CH₂) mā te whakamaroke.
2. Ka pāngia te etene e te tauhohenga tāpiri halogen hei whakaputa i te 1,2-dibromoethane.
3. Ka whakahaerehia te tango-halogenation hei whakaputa i te huringa ethyne.
4. ka puta te 2-butyne i te whakaroa tāpiri.
Mā te mārama ki ēnei tauhohenga ka tautoko i te otinga o ngā rapanga me ngā mahi whakaharatau i roto i ngā rangahau matū waro motuhake.
