Gas phase chiral molecules

Are there any molecules that are chiral that are also gases at room temperature? 


Failing that, what chiral molecules have a high vapor pressure? Propylene oxide has a boiling point of only 34 C, so that seems like a good one. Are there others?


EDIT: I appreciate all of the great suggestions! I should have mentioned before, but I am looking for something that can be purchased in both R and S enantiomers.




The molecule has to be small. *trans*-1,2-difluorocyclopropane is certainly chiral, and its predicted boiling point is ~ 5 deg C. *trans*-1,1,2,3-tetrafluorocyclopropane is another likely candidate. This one will be easier to prepare (from perfluoropropylene oxide and *trans*-1,2-difluoroethylene).


Separation of enantiomers is the hard part.


 5

[1-Chloro-1,2,2,2-tetrafluoroethane](http://en.wikipedia.org/wiki/1-Chloro-1,2,2,2-tetrafluoroethane) has bp -12 Celsium. For comparison, [1-chloro-1-fluoroethane](http://www.chemicalbook.com/ChemicalProductProperty_US_CB7446771.aspx) has bp +16 Celsium. In most cases, replacing good share of hydrogen in an organic molecule with fluorine leads to significant decrease of bp. [perfluoropropylene oxide](http://en.wikipedia.org/wiki/Hexafluoropropylene_oxide) has bp -27 Celsium, comparing to +34 of vanilla propylene oxide you noted.


 4

**Considering molecules that have been prepared and resolved:**


**1,3-dimethylallene** (2,3-pentadiene) boils a bit above room temperature at 48.5 C (see page 11 of this [reference](https://scholarspace.manoa.hawaii.edu/bitstream/handle/10125/11395/uhm_phd_6713714_r.pdf?sequence=1) for the experimental preparation), but likely has a reasonable vapor pressure since it has a lower molecular weight than pentane. The advantage to this molecule is that it has already been (at least) partially resolved (see [here](http://pubs.acs.org/doi/abs/10.1021/ja01026a032?journalCode=jacsat) and [here](http://www.sciencedirect.com/science/article/pii/S0040403900898305)) in a one-step hydroboration.


Another simple hydrocarbon to consider is ***trans*-cyclooctene**. It has a higher boiling point (143 C) but a significant vapor pressure, it flashes at 25 C. The molecule is chiral and has also been resolved.


 4

If you use deuterium and tritium, you can make stereocenters from methyl groups. For example, 1-deutero-1-tritioethane is be chiral.


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