Bestand wählen
Merken

The History of Main Group Chemistry

Zitierlink des Filmsegments
Embed Code

Automatisierte Medienanalyse

Beta
Erkannte Entitäten
Sprachtranskript
the way I read mom on the 1 Thai hard on her 10 at the time the what am today are being
asked to give you a little bit of an idea of some areas of chemistry that we're involved with and I thought it would be nice to give you the general rundown of the advances that have been made in the in the field of Maine group chemistry specifically over the last 20 to 30 years or so these these advances have been very rapid and so rapid in fact that this is a change in my group chemistry since the early 80's has been not to be the renaissance of
my chemistry has developed into an area now that I I like to call the modern-minded chemistry and so today I wanted to give you an idea of why these changes have occurred and what potential there are for the future of chemistry but I think if to do this it would be nice to have a little bit of a look at the historical aspects of manga chemistry not look into this a little bit of found that there are some direct and indirect links with the the chemistry department here and and maybe we can talk about that as well so organic talent chemistry obviously is involves the chemistry of compounds containing a bomb chemical bond between the main element and and Harvard and this field began actually 250 years ago this year contends that the 1st main group will get a metallic compound that was prepared was prepared in 1760 this is in fact the 1st example
of a organ metallic compound itself if you consider because the metal it's actually a sentimentalist supposed but this was prepared by the a French chemist called today to get a court and he he for whatever reason I decided to react potassium acetate with arsenic oxide this generated deep red foul-smelling liquid that few on exposure to air and this is commonly called as cold today's fuming liquid and was later found that this liquid comprise several components at 2 of which were taken Rafael Di Hossain said that is a compound containing announced becomes the belong to us think centers funded by to groups on the other ,comma component of main component was the oxide these companies called capped deal and captured deal oxide respectively and these names came not surprisingly from the foul stench of these very poisonous compounds and this is actually a fairly direct link between the capital and In today's fuming liquid with the chemistry department here at my work because I am in the mid 19th century a very famous professors from Harvard University Robert Townsend was looking into the components of this feeling like a trying to understand what the components of this liquid work and I think that sponsors won't moment I chemistry and notoriety attracted researchers from around Europe to come and work with him and 1 of those researchers was a young English chemist called Edward Franklin to many of you will know that that nite and Frankland came to the mother to carry out his PhD which he did in 1841 think and before he came to my father he was carrying out his own research and was looking at related research is looking at the the interaction of Metals Inc and vessels linked with zinc metal many found that these these reactions generated in both cases and mobile liquids which work with work part Forest far far too the spontaneously combusted in there but he didn't really know what these compounds were that during his time at mother thinking after he realized what they were and he found that they were actually diet sink and missiles Inc and if any of you have use these compounds using capital causing didn't you know how remarkably powerful work there as soon as they say here that burst into flames exposes an undergraduate chemist I was always amazed that in the mid 19th century people could handle these compounds and studies that we deal with our compounds all the time and we have to handle them under inert atmospheres we have general techniques for doing this using oxygen-free nitrogen for example or oxygen-free outgoing and Franklin Franklin himself had to use in the gas as well and and that's another thing I found remarkable about this Europe of history was the the inner guessed that he used was hydrogen so you can imagine that the potential here for explosions in his laboratory on the shortly before you actually had so this was the case in my view in during my undergraduate days was an interesting era in the history of mining group chemistry if you want to call it that it considers group element which many people so these compounds will relieve the forerunners of Granada we will know that Granada relations have formed from the reaction of outcome of all our highlights the magnesium metal there magnesium organ metallic compounds that had vast importance over the last 120 and 110 years and and they were developed by Victor Green in France and I think he won the Nobel Prize this chemistry and you know that's lighting well and again in my undergraduate days I carried out the undergraduate research project on the trying to develop Polly Grenier reagents so far and was quite heavily involved in Granada reagents and there in the synthesis and it surprised me at the time and still does that the that the mechanism of formation of these incredibly important reagents is still pretty much unknown there are a lot of theories out there on on how formed around and some evidence that the the definite mechanism in the formation of renewed reagents used in some this stuff but 1 theory that suggests that intermediates and the formation of these compounds containing magnesium magnesium bonds the alcohol magnesium magnesium Highlands and so formerly these compounds in the contains magnesium in the past 1 observations and said this is how we became involved in with our interests in low oxidation state magnesium company 25 later but that society will talk about the matter but the chemistry of the main group elements and fix was what becoming to be developed up to the stage the early part of the 20th century and then it was it was rapidly developed in the 1st half of the 20th century by the 3rd quarter of the 20th century and it was pretty well understood what my group chemists can do and how they behave what the properties and they became perhaps a little bit boring I would say all
the properties with 9 there's no surprises on offer their the compounds containing the S & P block elements contain those elements in either 1 or 2 oxidation states depending on whether the violence in SNP electrons were involved in bonding or just the violence the electrons were involved in bonding you could predict the coordination numbers of these compounds very well and a whole range of rules were developed in Britain if you like to pigeonhole the properties of my group will especially be blocked ,comma in 1 of these rules was the so called a double bond rule which told us real reassuringly that he could not form compounds containing multiple bonds between the 2nd and subsequent Rhode people look elements and I think a general belief in this rule led to stagnation in the chemistry of people locked element compounds in the in the lot in mid to late part of the 20th century and that was in contrast to the chemistry of transition metals which really rapidly developed in the 2nd half of the 20th century and my compounds are nearly always colorless they have 1 or 2 oxidation states they really don't behave in any catalytic behavior always transition metals nice colors they have variable oxidation states and we know that these properties are derived from their partial filling of their their violence the old rules and the closest energy spacing of these steel rules allows these compounds and then later these compounds being useful in for example catalysis which is hugely important area of chemistry women with transitional compounds you so In this this belief that my group compounds had perhaps not very interesting chemistry that persisted until the 80's and then I think in 1981 and in my view anyway this is where the changes renaissance in group chemistry occurred 3 important discoveries were made in that year they were firstly the development of the preparation of the 1st compound to contain a phosphorus carbon triple bond and this physical phosphor all Collins and this work was carried out by 2 German chemist cool and then go back and I think both of whom have associations will have had past associations with the chemistry department your mother and the there was the development of a compound containing carbon Double Bonus :colon forcefully formerly has phosphorus in the plus-one oxidation state and this was prepared by a Japanese chemist and of the future and finally the 1st example of a company containing silicon silicon double bond was made in 1991 to this is the silicon analog if you like all of the women outings and this was prepared by U.S. chemist Baldwin so I think once these compounds had to hit the literature if you like the general belief that some low oxidation state and or local ordination number 900 compounds that couldn't be formed was thrown out the window and there was an explosion in the area of the development of these compounds and obviously the species very reactive this generally they shouldn't exist thermodynamic fully they should either of the game arise they should disproportionate should be with oxygen etc. so used to prepare these comparison to stabilize kinetically generally a whole range of very bulky and alcohol are all in light of the gains were developed to attach these ligands to the medical centers in these companies to stop them and they can arising proportion for example and and this this allowed the development of a vast range of mental mental blunder compounds element element on the compounds huge clusters containing in some cases up to 84 per gallon actions chemistry developed much locals group at Karlsruhe and very fascinating compound types and I suppose some people will see these as new chemical curiosities but I think they have obviously there the high reactivity will lend them to having a number of applications and this is this is starting to develop no 1 took about minute but because all of these new compound types were being developed for example compounds with silicon silicon triple bombings germanium germanium double bonds final formerly 1 not formally but what what were described as I'm gallium triple belongs you new theoretical methods and bonding models needed to be developed to try and to try and understand the bonds between the elements in these compounds in a whole range of theoretical techniques have been developed to analyze the bonding and such compounds and this is really developed quite well except it's not fully developed yet and the analysis of the interpretation of the bonding in a lot of these systems has led to some vigorous debate in the literature let's say so it's very interesting to read a number of papers some people have views on on some compounds in the bombing in these companies 1 that this client gallantry proponents species that I meant mentioned that won't go into the specifics of the specifics of the competition but some people say it for example as having an ongoing triple bond summers annoying gallium double bond and summers on gallium single can see how controversy can be generated in these systems and time and again here there is a direct link with my father in what is your current professors cannot franking is I would say 1 of the world leaders in in analyzing the bonding and multiple bonded people compared to using theoretical methods so as I as I said that the chemistry of the Systems has developed rapidly over the last 20 25 years or so and and also as I said there probably viewed by the chemical community is largely being chemical curiosity very interesting compounds but not much use that has really changed a lot over the last 2 I would say 3 years there are a number of groups showing that these compounds of a high reactivity of these compounds can be used for useful purposes and I would say some of those groups of people pounds group that UC Davis adult Steffens Group in Toronto and Debor from group in UC Riverside and these groups are looking at using local water level oxidation state group compounds to activate small-molecule for example .period hydrogen ammonia and ethylene and this is this is never been done before for some Hodge ammonia that 1st activations of these important molecules with people Will oxidation state people come and really only occurred in the last 3 or 4 years and is now being shown in in some cases these excavations are actually reversible so I think it's quite obvious that such low oxidation state people or companies might find use in catalysis indeed someday they might even be able to replace transition metals in catalytic processes and we all know that most of the transition that was used in catalysis the very expensive ones so if we can replace those with extremely cheap people opulent competence then there's a definite used for such companies have our
our Arafat a little the other guy the
move
Chemische Forschung
Funktionelle Gruppe
Krankengeschichte
Computeranimation
Chemische Forschung
Biologisches Lebensmittel
Chemische Bindung
Querprofil
Funktionelle Gruppe
Chemisches Element
Chemische Verbindungen
Hauptgruppenelement
Aktionspotenzial
Inertgas
Alkohol
Metallatom
Kaliumacetat
Koordinationszahl
Fettsäuremethylester
Magnesium
Ligand
Stickstoff
Ionenbeweglichkeit
Doppelbindung
Stratotyp
Aktionspotenzial
Spezies <Chemie>
Übergangsmetall
Reaktionsmechanismus
Chemische Bindung
Atomcluster
Molekül
Lactitol
Dreifachbindung
Hauptgruppenelement
Ethylen
Krankengeschichte
Phosphor
Fleischersatz
Elektron <Legierung>
Fülle <Speise>
Reaktionsführung
Oxidschicht
Zink
Reaktivität
Organischer Halbleiter
Kompetenz <Bakteriologie>
Germane
Abschrecken
Explosion
Flamme
Chemische Forschung
Germanium
Kohlenstofffaser
Phosphonsäure
Explosivität
Elektrolytische Dissoziation
Chemische Verbindungen
Bathygraphie
Strom
Ammoniak
Nobelium
Atombindung
f-Element
Funktionelle Gruppe
Systemische Therapie <Pharmakologie>
Biosynthese
Hydrierung
Tiermodell
Wasserstand
Aktivität <Konzentration>
Querprofil
Silicone
Setzen <Verfahrenstechnik>
Arsen
Energiearmes Lebensmittel
Stickstofffixierung
Gallium
Chemische Eigenschaft
Oxide
Farbenindustrie
Pharmazie
Chemisches Element
Chemischer Prozess
Sauerstoffverbindungen
Ader <Geologie>
Vorlesung/Konferenz
Chemische Forschung
Funktionelle Gruppe
Krankengeschichte
Computeranimation
Vorlesung/Konferenz

Metadaten

Formale Metadaten

Titel The History of Main Group Chemistry
Serientitel Chymiatrie
Autor Jones, Cameron
Jerabek, Paul
Hegemann, Julian
Authmann, Andreas
Lizenz CC-Namensnennung - keine kommerzielle Nutzung - Weitergabe unter gleichen Bedingungen 3.0 Deutschland:
Sie dürfen das Werk bzw. den Inhalt zu jedem legalen und nicht-kommerziellen Zweck nutzen, verändern und in unveränderter oder veränderter Form vervielfältigen, verbreiten und öffentlich zugänglich machen, sofern Sie den Namen des Autors/Rechteinhabers in der von ihm festgelegten Weise nennen und das Werk bzw. diesen Inhalt auch in veränderter Form nur unter den Bedingungen dieser Lizenz weitergeben.
DOI 10.5446/18771
Herausgeber Paul Jerabek, Julian Hegemann, Andreas Authmann
Erscheinungsjahr 2010
Sprache Englisch

Inhaltliche Metadaten

Fachgebiet Chemie
Abstract Prof. Jones (Monash University, Australia) gives a short historical overview over the developments in main group chemistry.
Schlagwörter Vortrag
Anorganik

Zugehöriges Material

Ähnliche Filme

Loading...
Feedback