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'''Organoxenon compounds''' in [[organic chemistry]] contain [[carbon]] to [[xenon]] chemical bonds. The first organoxenon compounds were divalent, such as (C<sub>6</sub>F<sub>5</sub>)<sub>2</sub>Xe. The first tetravalent organoxenon compound, [C<sub>6</sub>F<sub>5</sub>XeF<sub>2</sub>][BF<sub>4</sub>], was synthesized in 2004.<ref name = XeIV>{{cite journal|coauthors=LeBlond, Nicolas, Lutar, Karel, Žemva, Boris|title=The First Organoxenon(IV) Compound: Pentafluorophenyldifluoroxenonium(IV) Tetrafluoroborate|journal=Angewandte Chemie International Edition|date=2000-01-16|volume=39|issue=2|pages=391–393|doi=10.1002/(SICI)1521-3773(20000117)39:2<391::AID-ANIE391>3.0.CO;2-U}}</ref> So far, more than one hundred organoxenon compounds have been researched. | |||
Most of the organoxenon compounds are more unstable than [[xenon fluoride]]s due to the high [[Chemical polarity|polarity]]. The molecular dipoles of xenon difluoride and [[xenon tetrafluoride]] are both 0 [[Debye|D]]. The early synthesized ones only contain perfluoro groups, but later some other groups were found, e.g. 2,4,6-trifluorophenyl.<ref name=XeII>{{cite journal|title=C6F5XeF, a versatile starting material in xenon-carbon chemistry|journal=Journal of Fluorine Chemistry|date=2004-05-31|volume=125|issue=6|pages=981–988|doi=10.1016/j.jfluchem.2004.01.019|last=FROHN|first=H}}</ref> | |||
== Xe(II) == | |||
The most common bivalent organoxenon compound is C<sub>6</sub>F<sub>5</sub>XeF, which is always used as a precursor to other organoxenon compounds. Due to the unstability of xenon fluoride, it is impossible to synthesize organoxenon compound by using general [[organic reagent]]s. Most frequently used [[fluorinating agent]]s include Cd(Ar<sub>F</sub>)<sub>2</sub>(subscript "F" means fluorine-including [[aryl]]), C<sub>6</sub>F<sub>5</sub>SiF<sub>3</sub>, and C<sub>6</sub>F<sub>5</sub>SiMe<sub>3</sub> (should be used along with fluoride). | |||
With the use of stronger [[Lewis acid]]s, such as C<sub>6</sub>F<sub>5</sub>BF<sub>2</sub>, [[ionic compound]]s like [RXe][Ar<sub>F</sub>BF<sub>3</sub>] can be produced. [[Alkenyl]] and [[alkyl]] organoxenon compounds are prepared in this way as well, for example, C<sub>6</sub>F<sub>5</sub>XeCF=CF<sub>2</sub> and C<sub>6</sub>F<sub>5</sub>XeCF<sub>3</sub>.<ref name=XeII /> | |||
Some typical reactions are listed below: | |||
:<math>\rm \ 2C_6F_5XeF + Cd(C_6F_5)_2 \rightarrow Xe(C_6F_5)_2 + CdF_2\downarrow </math> | |||
:<math>\rm \ C_6F_5XeF + Me_3SiCN \rightarrow C_6F_5XeCN + Me_3SiF</math> | |||
:<math>\rm \ C_6F_5XeF + Cd(2,4,6-C_6H_2F_3)_2 \rightarrow 2,4,6-C_6H_2F_3XeC_6F_5 + CdF_2\downarrow </math> | |||
The third reaction also produces (C<sub>6</sub>F<sub>5</sub>)<sub>2</sub>Xe, Xe(2,4,6-C<sub>6</sub>H<sub>2</sub>F<sub>3</sub>)<sub>2</sub> and so on. | |||
The precursor C<sub>6</sub>F<sub>5</sub>XeF can be prepared by the reaction of [[trimethyl(pentaflurophenyl)silane]](C<sub>6</sub>F<sub>5</sub>SiMe<sub>3</sub>) and [[xenon difluoride]]. Adding fluoride to the adduct of C<sub>6</sub>F<sub>5</sub>XeF and [[arsenic pentafluoride]] is another method.<ref name=XeII /> | |||
==Xe(IV)== | |||
In 2000, Karel Lutar and Boris Žemva ''et al.'' produced an ionic compound. They treated [[xenon tetrafluoride]] and [[difluoro(pentaflurophenyl)borane]] in dichloromethane at -55°C: | |||
:<math>\rm \ XeF_4 + C_6F_5BF_2 \xrightarrow[-55^oC]{CH_2Cl_2} [C_6F_5XeF_2]^+BF_4^-</math> | |||
The compound is an extremely strong [[fluorinating agent]], and it is capable of converting (C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>P to (C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>PF<sub>2</sub>, C<sub>6</sub>F<sub>5</sub>I to C<sub>6</sub>F<sub>5</sub>IF<sub>2</sub>, even iodine to [[iodine pentafluoride]].<ref name = XeIV /> | |||
== See also == | |||
* Compounds of carbon with other elements in the periodic table: | |||
{{ChemicalBondsToCarbon}} | |||
== References == | |||
{{reflist}} | |||
{{Xenon compounds}} | |||
{{Noble gas compounds}} | |||
[[Category:Xenon compounds]] |
Revision as of 09:02, 8 September 2012
Organoxenon compounds in organic chemistry contain carbon to xenon chemical bonds. The first organoxenon compounds were divalent, such as (C6F5)2Xe. The first tetravalent organoxenon compound, [C6F5XeF2][BF4], was synthesized in 2004.[1] So far, more than one hundred organoxenon compounds have been researched.
Most of the organoxenon compounds are more unstable than xenon fluorides due to the high polarity. The molecular dipoles of xenon difluoride and xenon tetrafluoride are both 0 D. The early synthesized ones only contain perfluoro groups, but later some other groups were found, e.g. 2,4,6-trifluorophenyl.[2]
Xe(II)
The most common bivalent organoxenon compound is C6F5XeF, which is always used as a precursor to other organoxenon compounds. Due to the unstability of xenon fluoride, it is impossible to synthesize organoxenon compound by using general organic reagents. Most frequently used fluorinating agents include Cd(ArF)2(subscript "F" means fluorine-including aryl), C6F5SiF3, and C6F5SiMe3 (should be used along with fluoride).
With the use of stronger Lewis acids, such as C6F5BF2, ionic compounds like [RXe][ArFBF3] can be produced. Alkenyl and alkyl organoxenon compounds are prepared in this way as well, for example, C6F5XeCF=CF2 and C6F5XeCF3.[2]
Some typical reactions are listed below:
The third reaction also produces (C6F5)2Xe, Xe(2,4,6-C6H2F3)2 and so on.
The precursor C6F5XeF can be prepared by the reaction of trimethyl(pentaflurophenyl)silane(C6F5SiMe3) and xenon difluoride. Adding fluoride to the adduct of C6F5XeF and arsenic pentafluoride is another method.[2]
Xe(IV)
In 2000, Karel Lutar and Boris Žemva et al. produced an ionic compound. They treated xenon tetrafluoride and difluoro(pentaflurophenyl)borane in dichloromethane at -55°C:
The compound is an extremely strong fluorinating agent, and it is capable of converting (C6F5)3P to (C6F5)3PF2, C6F5I to C6F5IF2, even iodine to iodine pentafluoride.[1]
See also
- Compounds of carbon with other elements in the periodic table:
Template:ChemicalBondsToCarbon
References
43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.
Template:Xenon compounds Template:Noble gas compounds
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A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running
The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more
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In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang
Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules
Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.
A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running
The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more
There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang