Elimination Reactions of Alcohols

April 16, 2015

Here’s a summary of what we talk about in today’s post. Hydrohalic acids (HX)  plus alcohols give substitution products… We just saw that treating an alcohol with a strong hydrohalic acid – think HCl, HBr, or HI – resulted in the formation of alkyl halides. With a tertiary alcohol like the one drawn below, this […]

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PBr3 and SOCl2

March 20, 2015

Lately we’ve been talking a lot about converting alcohols to good leaving groups [halides] [tosylates and mesylates] You might think we’d be done already, but not yet! In today’s post we talk about a third important method for converting alcohols to good leaving groups – by using the reagents phosphorus tribromide (PBr3) and thionyl chloride […]

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Tosylates And Mesylates

March 10, 2015

Today we’re going to talk about a different way of making alcohols into good leaving groups – by turning them into tosylates and mesylates (“organosulfonates”). Here’s a brief summary of what we’ll cover here: Making Alcohols Into Good Leaving Groups, Part 2 We’ve seen that alcohols are poor substrates for substitution reactions. The main problem is that […]

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Making Alkyl Halides From Alcohols

February 27, 2015

Making Alkyl Halides From Alcohols In today’s post we show that treating alcohols with HCl, HBr, or HI (which all fall under the catch-all term “HX” where X is a halide) results in the formation of alkyl halides. We’ve said many times in this series of posts that alcohols are poor substrates for SN1 and SN2 […]

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Opening Of Epoxide With Base

February 10, 2015

Opening of epoxides with base a summary of what we talk about today: In the last post we discussed the reactions of epoxides under acidic conditions and saw how they resembled the “3-membered ring” family of alkene mechanisms. We left off by noting that the reaction of the epoxide (shown above)  with NaOH in H2O […]

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Opening of Epoxides With Acid

February 2, 2015

Here’s what we’re covering in this post. Opening Epoxides With Aqueous Acid In the last post, we saw some examples of how epoxides are considerably more reactive towards breakage than are ordinary ethers. For example, aqueous acid [often abbreviated “H3O+”] will open an epoxide under MUCH milder conditions than an “ordinary” ether such as diethyl […]

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Epoxides – The Outlier Of The Ether Family

Epoxides – The Outlier Of The Ether Family

January 26, 2015

 In this post we discuss a special class of ethers that has unusually high reactivity due to their ring strain – epoxides. Here’s a summary of what we’ll talk about here:   In the last post, I wrote that ethers were quite possibly the most boring functional group of all, at least from the perspective of reactivity. […]

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Cleavage Of Ethers With Acid

November 19, 2014

I’ve been looking forward to today’s post for a long time! We’ve gone through so many different ways of synthesizing ethers, and finally we get to talk about all the exciting things we get to do with them. Here it is, the moment you’ve been waiting for. All the reactions of ethers in once place: […]

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Ether Synthesis Via Alcohols And Acid

November 14, 2014

Last post I got a little ahead of myself. I was all excited about getting into the reactions of ethers, and forgot that there’s one last method for ether synthesis that we haven’t covered. It’s actually not that general so you can likely skip ahead. But for the sake of completeness, here it is. Remember when we said […]

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Synthesis of Ethers (2) – Back To The Future

November 7, 2014

In the last two posts we’ve been discussing the Williamson synthesis of ethers. As we saw, our discussion was essentially a complete re-hash of everything we’d already said about the SN2 reaction that was covered several chapters ago. That’s the thing with organic chemistry – things you learn in the early stages of the course often […]

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