I have been reading through Philip J. Kocienski's book Protecting Groups to try to better understand some of the characteristics of hydroxy protecting groups. I am looking to understand the compatibility of silyl ethers, alkyl ethers, alkoxymethyl ethers, tetrahydropyranyl, methylthiomethyl ethers, esters, and carbonates with acidic conditions; however, my book is very vague on this. Which of these classes of protecting groups will be compatible with strongly acidic conditions (specifically, I will need it to remain intact in HBr for an addition reaction). I am just looking to know which categories are best for these conditions so I can narrow my search. So far, based on what I have read, the Troc protecting group would best suit strongly acidic conditions; however, it is highly electron withdrawling, which will likely affect an addition reaction I am looking to perform.
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1$\begingroup$ At what temperature will the HBr reaction be run? $\endgroup$ – Waylander Nov 11 at 8:04
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$\begingroup$ I will be running the reaction at -10 C in a 30% HBr-acetic acid solution in toluene (an adaption of the following protocol: pubs.acs.org/doi/pdf/10.1021/ed072p848). All future steps are also performed at -10 C. $\endgroup$ – ELI JONES Nov 11 at 14:27
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$\begingroup$ Plain old O-benzyl ether will probably stand that pretty well $\endgroup$ – Waylander Nov 11 at 14:55
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$\begingroup$ Well "protective groups" are not an absolute way of protecting a moiety. It always depends on the reaction conditions you will use later. $\endgroup$ – SteffX Nov 11 at 15:34
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$\begingroup$ I cannot use a benzyl ether since the product I have to deprotect (I've included an image above - the aliphatic -OH group will have the protecting group-) contains a benzyl ether moiety $\endgroup$ – ELI JONES Nov 11 at 15:45