Hot reactions proceed faster than cold reactions simply because the molecules have more energy, and also they collide more often. acidic or basic usually has to do with some sort of catalytic reaction IDK much aboot organic chem, so I will leave that question to other members.
I think that an excess of OH- in solution facilitates the reaction by cleaving the reduced manganese species off of the organic substrate. It's probably also necessary to initiate the final oxidation from aldehyde to carboxylic acid. In acidic solution then there wouldn't be any good nucleophiles, just water.
A primary alchol can become a carboxylic acid but the alchol needs an acidificed dichromate solution (e.g. potassium dichromate solution) or sulphuric acid (well simply concentrated acid). If I have understood the question, you are asking how to make a carboxylic from an alchol. So I would say it has to be acidic.
To make an alchol from an alkene does need a base for the electrophilic addition.
I read that acidic KMnO4 can also oxidize alcohols and aldehydes to carboxylic acids, so maybe the "basic" part isn't so important for that. I also read that hydroxide accelerates the cleavage of the manganese species after the dihydroxylation step of the alkene cleavage process. So, I would guess that the nucleophile is most important there.
The same effect is true with OsO4. If you use a stoichiometric amount of the osmium, then you have to do a workup that is capable of cleaving the osmium-organic complex before you can isolate the dihydroxylation product.
We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling We Value Civility
• Positive and compassionate attitudes
• Patience while debating We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving