All variations are fair game on the DAT. Know problems involving theory, stereochemistry, lab techniques, NMR, IR and various diagnostic tests. Know how to do reactions along with what reagents are involved. As we have stated many times, there are many different versions of the DAT, you MUST prepare accordingly.what kind of questions they ask on the exam? are they one step problems or multiple steps-like? are they once that asking for reagent? beginning product? end product?
Thank you for the thorough explanation!Be familiar with the reactions for alkanes, alkenes, alkynes, alcohols, benzenes, radicals, organometallics, carbonyl compounds (including aldehydes, ketones, and carboxylic acids and their derivatives), and especially alpha carbon reactions (e.g., the Wittig Reaction, Claisen Condensation, Aldol Condensation, and so forth). Malonic ester and acetoacetic ester synthesis are important reactions as well.
Also, have a firm understanding of the principles of aromaticity and resonance, the stability of carbocations, radicals, and anions, and molecular and hybridized orbitals, as well as predicting the sstrengths of acids and bases, and determining which proton on a molecule is the most acidic. I would also recommend memorizing the pKa values for the generic class of organic compounds (e.g., carboxylic acids have pKas of approximately 5, while ketones have pKas of about 19, with aldehydes somewhat lower, alcohols and water have pKas of approximately 15, amines 36, and so forth).
Make sure you can assign the correct structure to a molecule if given its C13 NMR spectrum. Often times these molecules tend to have similar functional groups, but differ in their connectivity, so it's not enough to merely know that, for example, carbonyl carbon signals appear in excess of ppm 160. Needless, to say you will need to have an understanding of stereochemistry and determining whether a configuration is R or S, and know that the only way we can determine whether a compound will rotate right left or right is by placing it in a polarimeter (and that if one rotates left, then the other must rotate right, but we cannot determine beforehand whether R or S will rotate left or right).
Lastly, be familiar with the various laboratory techniques and how they're used to separate and classify compounds or elucidate chemical structure (e.g., extractions, chromatography, melting points, and et cetera).
Proteins, nucleic acids, and lipids may also appear on the exam, and Chad's Videos as well as KBB covers these topics.
Note that not all of these topics will appear on your exam, but any of them may very well so. Undoubtedly, that means that you will study for things you will not encounter on the actual exam, but it is the only way you can be certain that you will prepared for the majority of what will show up on the test.