[rkiecaboose]

Hello I've been trapped on some questions on my homework and would VERY much appreciate help/explanations



Question 1b, I am actually completely clueless how as to what this structure is.
Question 2 and 3 involve the same chemical formula C9H10O3 which I'm assuming that both are aromatic compounds but the first one contains a COOH group while question 3 is an ester? I'm really lost on these two. SOLVED
As for the last two questions 4-5 I'm actually completely lost as I don't know the chemical formulas to even start?

[orgopete]

1b) Hint, how many chirality centers are in 1a?

4 & 5, I don't even know which they are? None the less, hydrogens come in 1s, 2s, and 3s. The integrals are shown. What pieces would you literally be putting together if you were assembling the structures with molecular models? For the structure with the MF, you know exactly how many carbons, hydrogens, and oxygens you are using. For the ones with the MW, you can still begin by adding together the CH_n or OH pieces you are given from the NMR. Subtract them from the MW and what is missing?

[rkiecaboose]

1b) There are two chiral centers in 1a but its not asking for an enatiomer or a diasteromer but an isomer?  So....I'm lost on this one still?

4/5 being the bottom questions that dont give the molecular formula:
 -#4 what functional group does that UV indicate?
  Are both of them aromatic?

[sjb]

1b) There are two chiral centers in 1a but its not asking for an enatiomer or a diasteromer but an isomer?  So....I'm lost on this one still?

Enantiomers and diasteromers are still isomers, just like association football, rugby union, Australian rules etc are still football....

[discodermolide]

1b) There are two chiral centers in 1a but its not asking for an enatiomer or a diasteromer but an isomer?  So....I'm lost on this one still?

4/5 being the bottom questions that dont give the molecular formula:
 -#4 what functional group does that UV indicate?
  Are both of them aromatic?

Suggestions for numbers 4 & 5

[rkiecaboose]

1b) There are two chiral centers in 1a but its not asking for an enatiomer or a diasteromer but an isomer?  So....I'm lost on this one still?

Enantiomers and diasteromers are still isomers, just like association football, rugby union, Australian rules etc are still football....

That's what I initially thought, but it's all coming out as wrong....perhaps the question is flawed as some of the other ones my professor put up were flawed.

Also I've already solved 4 and 5 Thank you!

[sjb]

1b) There are two chiral centers in 1a but its not asking for an enatiomer or a diasteromer but an isomer?  So....I'm lost on this one still?

Enantiomers and diasteromers are still isomers, just like association football, rugby union, Australian rules etc are still football....

That's what I initially thought, but it's all coming out as wrong....perhaps the question is flawed as some of the other ones my professor put up were flawed.

Imagine for instance inverting the stereochemistry of one of the chiral centres? Does this affect the equivalency of the methyl protons, for instance?

(edit to fix tags, sjb)

[orgopete]

…
Also I've already solved 4 and 5 Thank you!

Okay then. For anyone still trying to solve them, I believe they are:
Top right, 2-hydroxyethylbenzoate
Bottom left, (E)-hex-2-enoic acid
Bottom right, 3-(4-hydroxyphenyl)propanoic acid