Using Protecting Groups

Question 1

how can we form beta 1,4-glycosidic linkage between 2 glucoses?

Answer 1

nature: enzymes (not efficient in lab/large scale)

synthetically-difficult b/c stereochem, lots of OHs, solubility problems

Question 2

glycosyl donor

Answer 2

suitable L.G. necessary at C1

glycosyl halide activated by lewis base

this is E+

Question 3

glycosyl acceptor

Answer 3

need C-OH unprotected

all other OHs protected

this is Nu

Question 4

how to only form 1,4 Beta

Answer 4

neighboring group participation of C2 blocks bottom p-orbital of C1