Priority Groups Order

[LuckMC11]

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does anyone know the order of what priority groups should be ranked in terms of naming a molecule (for orgo)? i was getting confused from kaplan when they said OH had highest priority but then said carboxylic groups had highest priority (so lowest number).

 

[rnbaxter]

does anyone know the order of what priority groups should be ranked in terms of naming a molecule (for orgo)? i was getting confused from kaplan when they said OH had highest priority but then said carboxylic groups had highest priority (so lowest number).

I think you are asking about RS nomenclature. If you are you look at your chiral center. The highest priorty (1), is the first atom bonded to the chiral carbon with the highest atomic number.

 

[DQLEUCD]

does anyone know the order of what priority groups should be ranked in terms of naming a molecule (for orgo)? i was getting confused from kaplan when they said OH had highest priority but then said carboxylic groups had highest priority (so lowest number).

http://www.muhlenberg.edu/depts/chemistry/chem201woh/FGPRIORT.htm

For nomenclature it's that

For R/S, cis/trans, E/Z: whichever has the highest atomic number gets priority.

 

[LuckMC11]

I think you are asking about RS nomenclature. If you are you look at your chiral center. The highest priorty (1), is the first atom bonded to the chiral carbon with the highest atomic number.

thanks for this! but i was looking more for the response that DQLEUCD posted.

http://www.muhlenberg.edu/depts/chemistry/chem201woh/FGPRIORT.htm

For nomenclature it's that

For R/S, cis/trans, E/Z: whichever has the highest atomic number gets priority.

thanks so much for the link! however, i am kinda confused from what is given there. from the onium ion to the nitrile it decreases in priority right? but then what happens in the next set down, is it saying nitriles have higher priority than aldehydes and ketones?

 

[nyr201]

Carb acids>esters>amides>nitriles>aldehydes>ketones>alc>amines>ethers

 

[LuckMC11]

Carb acids>esters>amides>nitriles>aldehydes>ketones>alc>amines>ethers

oh ok i got it now thanks a ton!!

 

[DQLEUCD]

thanks for this! but i was looking more for the response that DQLEUCD posted.



thanks so much for the link! however, i am kinda confused from what is given there. from the onium ion to the nitrile it decreases in priority right? but then what happens in the next set down, is it saying nitriles have higher priority than aldehydes and ketones?

Yes, just follow the list and you'll be ok. The possibility of an onium ion being on the DAT is close to nill so don't worry about it. Just focus on the functional groups you learned about. I never even heard of it before so it's pretty safe to say that it won't be on the DAT's. Just focus on whatever groups you learned about in KBB and Chad's Vid's.