[Sealion]

Can anyone help me naming these isoflavones? I have attempted them

1.


2.



I have attempted them. For the first one I had:
6-chloro-7-hydroxy-3-(4-methoxyphenyl)chromen-4-one-3-carboxylic acid

Second one I had:
1-(3-chloro-4,6-dihydroxyphenyl)2-phenylethanoate

[Dan]

6-chloro-7-hydroxy-3-(4-methoxyphenyl)chromen-4-one-3-carboxylic acid

Are the methoxyphenyl and carboxylic acid groups both on the same position (3) in the structure you posted?

Second one I had:
1-(3-chloro-4,6-dihydroxyphenyl)2-phenylethanoate

Ethanoate means this carboxylate:



It is not present in your structure.

Hint: Your parent structure is a ketone, not a carboxylate.

[Sealion]

Are the methoxyphenyl and carboxylic acid groups both on the same position (3) in the structure you posted?

So for the first one,
6-chloro-7-hydroxy-3-(4-methoxyphenyl)chromen-4-one-2-carboxylic acid (?)

Ethanoate means this carboxylate:



It is not present in your structure.

Hint: Your parent structure is a ketone, not a carboxylate.

I am actually not sure on where to start for this one because it does not have a typical isoflavone structure 
Also naming the chlorodihydroxyphenyl group I am not sure where to start, would it be 1 on where the ring connects to the ketone?
This is embarassing but I can't tell if it is a methone, propanone or butone...
But I have attempted it again, I am guessing it is either

1-(3-chloro-4-6-dihydroxyphenyl)3-phenyl-propan-1-one
or
1-phenyl-3-(3-chloro-4,6-dihydroxyphenyl)propan-1-one

[Dan]

So for the first one,
6-chloro-7-hydroxy-3-(4-methoxyphenyl)chromen-4-one-2-carboxylic acid (?)

Looks good to me

Also naming the chlorodihydroxyphenyl group I am not sure where to start, would it be 1 on where the ring connects to the ketone?

Yes

This is embarassing but I can't tell if it is a methone, propanone or butone...

It's none of those! Draw the structure out, circle the phenyl group and circle the chlorodihydroxyphenyl group. Count how many carbons are left. What is the appropriate name?

[Sealion]

Looks good to me

Cheers! 

It's none of those! Draw the structure out, circle the phenyl group and circle the chlorodihydroxyphenyl group. Count how many carbons are left. What is the appropriate name?

So is it
4-phenyl-1-(3-chloro-4,6-dihydroxyphenyl)butan-2-one (?)

[Dan]

No, it's not a butanone derivative. But means four.

Hint:

What is this called?


So what is this called?

[Sealion]

Hi Dan,
Sorry late response, I have had a lot of things to do lately!

No, it's not a butanone derivative. But means four.

Hint:

What is this called?

This is ethane

So what is this called?

This is 1,2-diphenylethane

So with this in mind, the isoflavone in question must be

1-phenyl-2-(3-chloro-4,6-dihydroxyphenyl)ethan-2-one (from right to left)
or
2-phenyl-1-(3-chloro-4,6-dihydroxyphenyl)ethan-1-one (from left to right)

I am inclined to say the latter because we always 'start' from the side with the least C atoms when naming functional groups such as ketones (sorry poor wording), not entirely sure though

[Dan]

1-phenyl-2-(3-chloro-4,6-dihydroxyphenyl)ethan-2-one (from right to left)
or
2-phenyl-1-(3-chloro-4,6-dihydroxyphenyl)ethan-1-one (from left to right)

Getting closer now, but there are still problems.

First: You should choose the name with the lowest locant numbers (the second one is better than the first for this reason)
Second: You should order the substituents alphabetically (phenyl and chlorodihydroxyphenyl)
Third: Consider lowest locants for the naming of the chlorodihydroyphenyl group. You current name (3-chloro-4,6-dihydroxyphenyl) is not the preferred name - there is another way to number it such that the combined locant numbers are smaller.

[Sealion]

Getting closer now, but there are still problems.

First: You should choose the name with the lowest locant numbers (the second one is better than the first for this reason)
Second: You should order the substituents alphabetically (phenyl and chlorodihydroxyphenyl)
Third: Consider lowest locants for the naming of the chlorodihydroyphenyl group. You current name (3-chloro-4,6-dihydroxyphenyl) is not the preferred name - there is another way to number it such that the combined locant numbers are smaller.

I did not know any of those rules, today I learned. I had a really rubbish A-level Chemistry teacher, my school and department were underfunded (the school is actually closing!)...

Anyway back on topic:
1-(5-chloro-2,4-dihydroxyphenyl)-2-phenyl-ethan-1-one

[Dan]

1-(5-chloro-2,4-dihydroxyphenyl)-2-phenyl-ethan-1-one

Good, well done. The only last minor thing is an unnecessary hyphen (which I highlighted in red)

IUPAC name is 1-(5-chloro-2,4-dihydroxyphenyl)-2-phenylethan-1-one

[Sealion]

Thank you ever so much Dan
Here's a snack!