Ukusetyenziswa okuNxulubilikayo kweSodium Cyanide kwi-Organic Synthesis

intshayelelo

Sodium i-cyanide (I-NaCN), kunye ne-chemical formula i-NaCN, i-crystalline eqinile emhlophe okanye i-powder enyibilikayo kakhulu emanzini kwaye inevumba elibi, elikrakra le-almond. Ngenxa ye-reactivity ephezulu, ifumene ukusetyenziswa okubanzi kuluhlu olubanzi lwe Ukuhlanganiswa kwendalo iimpendulo. Nangona kunjalo, kubalulekile ukuqaphela oko sodium cyanide iyityhefu kakhulu kwaye kufuneka iphathwe ngononophelo olukhulu kwaye ngokungqongqo ngokwemigaqo yokhuseleko. Eli nqaku liphonononga usetyenziso olwahlukeneyo lwe Isodium cyanide kwi-organic synthesis.

Usetyenziso kwi-Organic Synthesis

Ukusabela kweStrecker

Enye yezona zicelo ezaziwa kakhulu ze Isodium cyanide kwi-organic synthesis kwi-Strecker reaction. Le mpendulo yindlela enamandla yokwenza i-α - amino acids. Kwi-reaction ye-Strecker, i-aldehyde okanye i-ketone ithatha i-ammonium chloride (NH₄Cl) kunye ne-sodium cyanide. Indlela yokusabela ngokubanzi ngolu hlobo lulandelayo:

1. Okokuqala, i-aldehyde okanye i-ketone idibana ne-ammonia (eyenziwe kwi-situ evela kwi-ammonium chloride) ukuze yenze i-imine. ICarbonIqela le-yl le-aldehyde okanye i-ketone liyaprotonated, nto leyo eyenza ukuba libe ne-electrophilic ngakumbi. Emva koko, i-ammonia ihlasela i-carbonyl carbon eprotonated, ilandelwe yi-deprotonation ukuze yenze i-imine.

2. Emva koko, i-cyanide ion (CN⁻) evela kwi-sodium cyanide isebenza njenge-nucleophile kwaye ihlasela i-imine carbon. Oku kwenza i-α - i-amino nitrile ephakathi.

3. Ekugqibeleni, i-hydrolysis ye-α - i-amino nitrile phantsi kwe-acidic okanye iimeko ezisisiseko zivelisa i-α ehambelanayo - i-amino acid.

I-Strecker reaction ibonelela ngendlela ethe ngqo yokwazisa zombini iqela le-amino kunye neqela le-carboxyl (emva kwe-hydrolysis ye-nitrile) kwi-athomu ye-carbon enye, ebalulekileyo ekudityanisweni kwee-amino acids, iibhloko zokwakha iiprotheni. Ngokomzekelo, xa i-formaldehyde (HCHO) isabela nge-ammonium chloride kunye ne-sodium cyanide, ilandelwa yi-hydrolysis, i-glycine (NH₂CH₂COOH), i-amino acid elula, inokufumaneka.

Ukulungiswa kweeNitriles

I-sodium cyanide isetyenziswa ngokuqhelekileyo ukulungiselela i-nitriles. Kwi-substitution reaction, i-alkyl halides (efana ne-methyl bromide, i-CH₃Br) isabela nge-sodium cyanide kwi-solvent ye-polar aprotic efana ne-dimethyl sulfoxide (DMSO) okanye i-acetone. Ukusabela kuqhubeka ngendlela ye-SN2, apho i-ion ye-cyanide ihlasela i-athomu yekhabhoni ebotshelelwe kwi-halogen. I-athomu ye-halogen iyasuswa, kwaye i-alkyl nitrile yenziwa. Njengokuba:

CH₃Br + NaCN → CH₃CN + NaBr

I-Aryl nitriles inokuphinda yenziwe kusetyenziswa i-sodium cyanide kwiimeko ezithile. Ngokomzekelo, kwezinye iinguqu - i-metal-catalyzed reactions, i-aryl halides inokusabela kunye ne-sodium cyanide phambi kwe-catalyst efana ne-copper (I) cyanide (CuCN) okanye i-palladium catalysts. Le ndlela yokusabela ivumela ukwaziswa kweqela elisebenzayo le-CN kwiringi enuka kamnandi, eluncedo ekudityanisweni kwamachiza ahlukeneyo, amachiza agrogriswayo, kunye nedayi.

I-Benzoin Condensation

I-benzoin condensation yenye indlela ebalulekileyo yokusabela apho i-sodium cyanide idlala indima ebalulekileyo. Kule mpendulo, i-aldehydes enevumba elimnandi (i-aldehydes enendandatho enevumba elimnandi, efana ne-benzaldehyde, C₆H₅CHO) isabela phambi kobuninzi be-catalytic ye-sodium cyanide kwisisombululo esinxilisayo. Indlela yokusabela ibandakanya la manyathelo alandelayo:

1. I-cyanide ion iqala yongeza kwi-carbonyl carbon ye-benzaldehyde, esebenza njenge-nucleophile. Le mveliso yokongeza yicyanohydrin - efana nephakathi.

2. Umrhumo ongalunganga kwi-athomu ye-oksijini ye-cyanohydrin - njenge-intermediate inokuhlasela i-carbonyl carbon ye-benzaldehyde molekyuli.

3. Emva koluhlu lwamanyathelo okudlulisa iproton kunye nokupheliswa kwe-ion ye-cyanide, i-benzoin (α - i-hydroxy - ketone) yenziwe.

I-benzoin condensation ibonelela ngendlela yokwenza i-carbon entsha-carbon bond phakathi kweemolekyuli ezimbini ze-aldehyde, ezixabisekileyo ekuhlanganiseni iimolekyuli ze-organic eziyinkimbinkimbi. Nangona kwiminyaka yakutshanje, iinzame zenziwe zokutshintsha i-sodium cyanide kunye ne-catalysts ehambelana nokusingqongileyo njengetyuwa ye-thiazolium okanye i-vitamin B₁, indlela yendabuko yokusebenzisa i-sodium cyanide isasebenza kwezinye iimeko.

Iimpendulo ezongeziweyo kwiiNcoma ezingaxutywanga

I-sodium cyanide inokuthatha inxaxheba kwiimpendulo ezongezelelweyo kwiikhompawundi ezingaxutywanga. Ngokomzekelo, phambi kwe-catalyst, inokongeza kwi-α, β - i-unsaturated carbonyl compounds (njenge-acrolein, CH₂=CHCHO). Ukusabela kulandela uMichael - uhlobo lokudibanisa indlela, apho i-ion yecyanide ihlasela i-β - carbon ye-α,β - i-unsaturated carbonyl compound. Le mpendulo ingasetyenziselwa ukwazisa iqela le-cyanomethyl (-CH₂CN) kwi-system unsaturated, enokuthi iguqulwe ngakumbi ibe ngamanye amaqela asebenzayo. Ngokomzekelo, imveliso ephumayo inokuthi ifakwe i-hydrolyzed ukwenza i-carboxylic acid okanye iyancipha ukwenza i-amine.

Iingqwalaselo zoKhuseleko

Njengoko bekutshiwo ngaphambili, i-sodium cyanide inetyhefu kakhulu. Ukuphefumla, ukungeniswa, okanye ukudibana kwesikhumba nesodium cyanide kunokubulala. Idibana neeasidi ukuvelisa ihydrogen cyanide (HCN), irhasi enetyhefu kakhulu. Xa uphatha i-sodium cyanide, la manyathelo okhuseleko alandelayo kufuneka athotyelwe ngokungqongqo:

1. Sebenzisa kwindawo engena umoya kakuhle ukunqanda ukwakheka kweegesi eziyityhefu.

2. Nxiba izixhobo ezifanelekileyo zokuzikhusela, kuquka iiglavu, iiglasi, kunye nedyasi yelebhu. Kwezinye iimeko, kusenokufuneka isixhobo sokuphefumla.

3. Gcina i-sodium cyanide kwindawo ekhuselekileyo, ebhalwe phantsi kwi-acids kunye nezinye iikhemikhali ezisebenzayo.

4. Yiba nezicwangciso ezifanelekileyo zokusabela kwimeko yonxunguphalo kunye nezixhobo ezifanelekileyo kwimeko yokuchitheka okanye iingozi.

isiphelo

I-sodium cyanide yi-reagent eguquguqukayo kwaye ibalulekileyo kwi-organic synthesis. Ivumela ukusekwa kwamaqela ahlukeneyo asebenzayo abalulekileyo afana ne-amino acids, i-nitriles, kunye ne-α - i-hydroxy - i-ketones, kwaye ithatha inxaxheba kwi-carbon - carbon bond - ukwenza iimpendulo ezibalulekileyo. Nangona i-toxicity yayo, xa iphathwa ngononophelo olukhulu kunye nokuthotyelwa kwemimiselo yokhuseleko, iyaqhubeka iyisixhobo esibalulekileyo kwi-toolkit ye-synthetic chemist yokulungiswa koluhlu olubanzi lwee-organic compounds, ukusuka kwi-pharmaceuticals ukuya kwiikhemikhali ezintle. Nangona kunjalo, iinzame zophando eziqhubekayo zijolise ekuphuhliseni ezinye iindlela, iindlela ezikhuselekileyo zokuphumeza iinjongo ezifanayo zokwenziwa.