Hemijska sinteza — разлика између измена
Садржај обрисан Садржај додат
м pravljenje sablona Cite book |
. |
||
Ред 1:
{{short description|Planned series of chemical reactions to produce a desired substance}}{{рут}}
'''Hemijska sinteza''' je namensko izvršavanje [[hemijska reakcija|hemijskih reakcija]] s ciljem formiranja jednog ili više proizvoda. Ovaj proces tipično obuhvata niz [[fizika|fizičkih]] i hemijskih manipulacija. Pod modernim [[laboratorija|laboratorijskim]] uslovima, hemijski sintetički procesi su ponovljivi i pouzdani.<ref name="Clayden1st">{{Clayden1st}}</ref><ref name="ParkesNeorganskaHemija">{{ParkesNeorganskaHemija}}</ref>▼
▲'''Hemijska sinteza''' je namensko izvršavanje [[hemijska reakcija|hemijskih reakcija]] s ciljem formiranja jednog ili više proizvoda. Ovaj proces tipično obuhvata niz [[fizika|fizičkih]] i hemijskih manipulacija. Pod modernim [[laboratorija|laboratorijskim]] uslovima, hemijski sintetički procesi su ponovljivi i pouzdani.<ref name="Clayden1st">{{Clayden1st}}</ref><ref name="ParkesNeorganskaHemija">{{ParkesNeorganskaHemija}}</ref> As a topic of [[chemistry]], '''chemical synthesis ('''or '''combination)''' is the artificial execution of [[chemical reaction]]s to obtain one or several [[product (chemistry)|product]]s.<ref name=vogel /> This occurs by [[physics|physical]] and chemical manipulations usually involving one or more reactions. In modern [[laboratory]] uses, the process is [[reproducible]] and reliable.
Hemijska sinteza počinje sa selekcijom [[hemijsko jedinjenje|jedinjenja]] koja se nazivaju [[reagens]]i ili reaktanti. [[Lista reakcija|Razni tipovi reakcija]] se mogu primeniti u sintezi produkata, ili intermedijara. Da bi došlo do reakcije neophodno je da se reaktanti pomešaju u reakcionom sudu kao što je [[hemijski reaktor]] ili jednostavni [[Balon (laboratorijski pribor)|balon]]. Kod mnogih reakcija je neophodno da se primeni neki oblik post-reakcione procedure da bi se izolovao finalni proizvod.<ref name=vogel>Vogel, A.I., Tatchell, A.R., Furnis, B.S., Hannaford, A.J. and P.W.G. Smith. ''Vogel's Textbook of Practical Organic Chemistry, 5th Edition''. Prentice Hall. {{page|year=1996|isbn=978-0-582-46236-6}}.</ref> Količina proizvoda u hemijskoj sintezi se naziva prinosom reakcije. Tipično se hemijski prinos izražava u težinskim jedinicama (npr. [[gram]]ima) ili kao procenat totalne teoretske količine produkta. ''Sporedna reakcija'' je neželjena hemijska reakcija koja umanjuje prinos željenog produkta.▼
▲Hemijska sinteza počinje sa selekcijom [[hemijsko jedinjenje|jedinjenja]] koja se nazivaju [[reagens]]i ili reaktanti. [[Lista reakcija|Razni tipovi reakcija]] se mogu primeniti u sintezi produkata, ili intermedijara. Da bi došlo do reakcije neophodno je da se reaktanti pomešaju u reakcionom sudu kao što je [[hemijski reaktor]] ili jednostavni [[Balon (laboratorijski pribor)|balon]]. Kod mnogih reakcija je neophodno da se primeni neki oblik post-reakcione procedure da bi se izolovao finalni proizvod.<ref name=vogel>
The amount produced by chemical synthesis is known as the ''[[Yield (chemistry)|reaction yield]]''. Typically, yields are expressed as a [[mass]] in [[gram]]s (in a laboratory setting) or as a percentage of the total theoretical quantity that could be produced based on the [[limiting reagent]]. A ''[[side reaction]]'' is an unwanted chemical reaction occurring which reduces the desired yield. The word ''synthesis'' was used first in a chemical context by the chemist [[Hermann Kolbe]].<ref>{{cite journal|last=Kolbe|first=H.|year=1845|title=Beiträge zur Kenntniss der gepaarten Verbindungen|journal=Annalen der Chemie und Pharmacie|volume=54|issue=2|pages=145–188|doi=10.1002/jlac.18450540202|issn=0075-4617|url=https://zenodo.org/record/1426998}}</ref>
== Strategije ==
Many strategies exist in chemical synthesis that are more complicated than simply converting a [[reactant]] A to a reaction product B directly. For '''multistep synthesis''', a chemical compound is synthesized by a series of individual chemical reactions, each with its own work-up.<ref>{{cite book|last1=Carey|first1=Francis A.|last2=Sundberg|first2=Richard J.|year=2013|title=Advanced Organic Chemistry Part B: Reactions and Synthesis|publisher=Springer}}</ref> For example, a laboratory synthesis of [[Paracetamol#Synthesis|paracetamol]] can consist of three sequential parts. For [[cascade reaction]]s, multiple chemical transformations occur within a single reactant, for [[multi-component reaction]]s as many as 11 different reactants form a single reaction product and for a "[[telescopic synthesis]]" one reactant experiences multiple transformations without isolation of intermediates.
== Organske sinteze ==
{{main-lat|Organska sinteza|biohemija}}
[[Organic synthesis]] is a special type of chemical synthesis dealing with the synthesis of [[organic compound]]s. For the [[total synthesis]] of a complex product, multiple procedures in sequence may be required to synthesize the product of interest, requiring a large amount of time. Skill in organic synthesis is prized among chemists and the synthesis of exceptionally valuable or difficult compounds has won chemists such as [[Robert Burns Woodward]] a [[Nobel Prize for Chemistry]]. If a chemical synthesis starts from basic laboratory compounds, it is considered a purely synthetic process. If it starts from a product isolated from plants or animals and then proceeds to new compounds, the synthesis is described as a [[semisynthetic]] process.
=== Metodologija i primene ===
Each step of a synthesis involves a [[chemical reaction]], and [[reagent]]s and conditions for each of these reactions must be designed to give an adequate yield of pure product, with as few steps as possible.<ref>{{cite book | last = March | first = J. |author2=Smith, D. | title = Advanced Organic Chemistry, 5th ed | publisher = [[John Wiley & Sons|Wiley]] | year = 2001 | location = New York }}</ref> A method may already exist in the literature for making one of the early synthetic intermediates, and this method will usually be used rather than an effort to "reinvent the wheel". However, most intermediates are compounds that have never been made before, and these will normally be made using general methods developed by methodology researchers. To be useful, these methods need to give high [[Yield (chemistry)|yields]], and to be reliable for a broad range of [[Substrate (chemistry)|substrate]]s. For practical applications, additional hurdles include industrial standards of safety and purity.<ref>{{cite journal | author = Carey, J.S. | author2 = Laffan, D. | author3 = Thomson, C. | author4 = Williams, M.T. | year = 2006 | title = Analysis of the reactions used for the preparation of drug candidate molecules | journal = Org. Biomol. Chem. | volume = 4 | issue = 12| pages = 2337–2347 | doi = 10.1039/B602413K | url = https://semanticscholar.org/paper/5b27f82f2e7bd7365491988eb063e78b250e0b1d| pmid=16763676}}</ref>
Methodology research usually involves three main stages: ''[[Discovery (observation)|discovery]]'', ''[[Process optimization|optimisation]]'', and studies of ''scope and limitations''. The ''discovery'' requires extensive knowledge of and experience with chemical reactivities of appropriate reagents. ''Optimisation'' is a process in which one or two starting compounds are tested in the reaction under a wide variety of conditions of [[temperature]], [[solvent]], [[reaction time]], etc., until the optimal conditions for product yield and purity are found. Finally, the researcher tries to extend the method to a broad range of different starting materials, to find the scope and limitations. Total syntheses (see above) are sometimes used to showcase the new methodology and demonstrate its value in a real-world application.<ref>{{Cite journal|last=Nicolaou|first=K. C.|last2=Hale|first2=Christopher R. H.|last3=Nilewski|first3=Christian|last4=Ioannidou|first4=Heraklidia A.|date=2012-07-09|title=Constructing molecular complexity and diversity: total synthesis of natural products of biological and medicinal importance|journal=Chemical Society Reviews|language=en|volume=41|issue=15|doi=10.1039/C2CS35116A|pmid=22743704|issn=1460-4744|pages=5185–5238|pmc=3426871}}</ref> Such applications involve major industries focused especially on polymers (and plastics) and pharmaceuticals. Some syntheses are feasible on a research or academic level, but not for industry level production. This may lead to further modification of the process. <ref>{{Cite journal|last=Chen|first=Weiming|last2=Suo|first2=Jin|last3=Liu|first3=Yongjian|last4=Xie|first4=Yuanchao|last5=Wu|first5=Mingjun|last6=Zhu|first6=Fuqiang|last7=Nian|first7=Yifeng|last8=Aisa|first8=Haji A.|last9=Shen|first9=Jingshan|date=2019-03-08|title=Industry-Oriented Route Evaluation and Process Optimization for the Preparation of Brexpiprazole|journal=Organic Process Research & Development|volume=23|issue=5|pages=852–857|doi=10.1021/acs.oprd.8b00438|issn=1083-6160}}</ref>
== Neorganska sinteza ==
Neorganska sinteza and organometallic synthesis are applied to the preparation of compounds with significant non-organic content. An illustrative example is the preparation of the anti-cancer drug [[cisplatin]] from [[potassium tetrachloroplatinate]].<ref name=Alderden>{{cite journal|last1=Alderden|first1=Rebecca A.|last2=Hall|first2=Matthew D.|last3=Hambley|first3=Trevor W.|title=The Discovery and Development of Cisplatin|journal=[[J. Chem. Educ.]]|date=1 May 2006|volume=83|issue=5|page=728|doi=10.1021/ed083p728|bibcode=2006JChEd..83..728A}}</ref>
[[File:Cisplatin synthesis.svg|center|600px]]
== Druga značenja ==
Линија 14 ⟶ 37:
== Reference ==
{{reflist|
== Spoljašnje veze ==
* [http://www.synarchive.com Arhiva organske sinteze]
* [http://www.chem.wisc.edu/areas/reich/syntheses/syntheses.htm Sinteza prirodnih proizvoda]
* [https://organicchemistrydata.org/hansreich/resources/syntheses Natural product syntheses]
{{L|Гране хемије}}
{{Authority control-lat}}
{{DEFAULTSORT:Хемијска синтеза}}
[[Категорија:Хемијска синтеза]]
| |||