Desert Island Protecting Groups

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Choosing a good protecting group for your molecule can save a lot of time. The choices, however, are often overwhelming (T. Green, Protecting Groups in Organic Synthesis). Protecting groups are listed below in order of popularity.

Protecting group	Use this often	Use this sometimes	Avoid using this		I use this...
t-butyldimethylsilyl (TBS or TBDMS)	110	30	5	often	sometimes	avoid
t-butoxycarbonyl (BOC)	86	32	4	often	sometimes	avoid
benzyl	60	36	7	often	sometimes	avoid
benzyloxycarbonyl (CBZ)	40	38	9	often	sometimes	avoid
acetyl	42	41	13	often	sometimes	avoid
p-methoxybenzyl (PMB)	32	27	13	often	sometimes	avoid
triisopropylsilyl (TIPS)	22	19	7	often	sometimes	avoid
t-butyldiphenylsilyl (TBDPS)	21	18	6	often	sometimes	avoid
methyl ester	8	2	0	often	sometimes	avoid
9-fluorenyl methyloxycarbonyl (FMOC)	21	21	15	often	sometimes	avoid
Trimethylsilane (TMS)	19	27	14	often	sometimes	avoid
1,3-dioxolane	4	1	1	often	sometimes	avoid
dioxolane	5	1	3	often	sometimes	avoid
Trifluoroacetyl	3	0	2	often	sometimes	avoid
triethylsilyl (TES)	1	0	0	often	sometimes	avoid
2,2-dimethoxypropane	1	1	1	often	sometimes	avoid
allyl ester	1	3	1	often	sometimes	avoid
allyloxycarbonyl (alloc)	7	7	8	often	sometimes	avoid
t-butyl ester	2	4	3	often	sometimes	avoid
Trichloroacetyl	1	1	2	often	sometimes	avoid
benzylidene	5	9	6	often	sometimes	avoid
TEOC 2-(trimethylsilyl) ethoxycarbonyl	1	3	4	often	sometimes	avoid
isopropylidene	4	9	8	often	sometimes	avoid
pivaloyl	11	29	16	often	sometimes	avoid
trityl	7	22	14	often	sometimes	avoid
1,2 or 1,3 dithiane	4	7	14	often	sometimes	avoid
beta-methoxyethoxymethyl chloride	3	5	14	often	sometimes	avoid
SEM 2 (trimethylsilyl) ethoxymethane	11	11	23	often	sometimes	avoid
TMSE 2 (trimethylsilyl) ethyl	2	9	14	often	sometimes	avoid
methoxymethyl (MOM)	10	30	22	often	sometimes	avoid
trichloroethoxycarbonyl (Troc)	6	15	19	often	sometimes	avoid
tetrahydropyranyl (THP)	11	30	28	often	sometimes	avoid
2-naphthylmethyl (NAP)	4	8	22	often	sometimes	avoid
methyl	13	18	37	often	sometimes	avoid