Sometimes it is necessary in solid-phase peptide synthesis to use a resin linker that is more sensitive

Question:

Sometimes it is necessary in solid-phase peptide synthesis to use a resin linker that is more sensitive (that is, more reactive) to acid than the linker shown in Eq. 26.21 on p. 1285. The following group (blue) is one such linker. Explain why the peptide can be removed from this linker with much more dilute acid than is required for the linker in Eq. 26.21.