stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are...
Transcript of stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are...
![Page 1: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/1.jpg)
StereochemistrySome compounds can exist as a pair of mirror-‐image forms
![Page 2: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/2.jpg)
Some compounds can exist as a pair of mirror-‐image forms
![Page 3: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/3.jpg)
Some compounds can exist as a pair of mirror-‐image forms
![Page 4: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/4.jpg)
Chiral molecules have no plane of symmetry
![Page 5: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/5.jpg)
Stereogenic centres
![Page 6: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/6.jpg)
Stereogenic centres
![Page 7: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/7.jpg)
Many chiral molecules are present in nature as single enan:omers
![Page 8: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/8.jpg)
R and S can be used to describe the confi gura:on of a chiral centre
Is there a chemical difference between two enan:omers?
![Page 9: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/9.jpg)
The rota:on of plane-‐polarized light is known as op:cal ac:vity
![Page 10: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/10.jpg)
Enan:omers can be described as (+) or (–)
Enan:omers can be described as D or L
![Page 11: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/11.jpg)
Diastereoisomers are stereoisomers that are not enan:omers
![Page 12: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/12.jpg)
Diastereoisomers can be chiral or achiral
![Page 13: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/13.jpg)
Absolute and rela:ve stereochemistry
![Page 14: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/14.jpg)
Diastereoisomers can arise when structures have more than one stereogeniccentre
![Page 15: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/15.jpg)
Diastereoisomers can arise when structures have more than one stereogenic centre
![Page 16: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/16.jpg)
Why only usually?—achiral compounds with more than one stereogenic centre
![Page 17: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/17.jpg)
Inves:ga:ng the stereochemistry of a compound
![Page 18: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/18.jpg)
Chiral compounds with no stereogenic centres
![Page 19: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/19.jpg)
Axes and centres of symmetry
![Page 20: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/20.jpg)
Axes and centres of symmetry
![Page 21: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/21.jpg)
Separa:ng enan:omers is called resolu:on
![Page 22: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/22.jpg)
Separa:ng enan:omers is called resolu:on
![Page 23: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/23.jpg)
Resolu:ons using diastereoisomeric salts
![Page 24: stereochemistry - uniurb.it · NC CN Enantiomers and chirality OH HO CN the enantiomers A and B are formed in exactly equal amounts Enantiomers are structures that are not identical,](https://reader030.fdocuments.net/reader030/viewer/2022021423/5aea3e0e7f8b9a90318b5f94/html5/thumbnails/24.jpg)
Resolu:ons can be carried out by chromatography on chiral materials