A Route to Carbasugar Analogues - Jonathan Clayden - The ...

Chapter 2 – Dearomatising additions to aryl oxazolines
These results show that both the presence of the DMPU co-solvent and the nature of
the oxazoline are important. To see if the reaction could be further improved, a
number of other 2-aryloxazolines were made from chiral pool amino alcohols (the
synthesis of oxazolines is discussed in section 3.1) and treated to the reaction
conditions.
i) NuLi (1.5 eq)
DMPU (6 eq), THF
ii) MeI
Me
Nu
R
R
Ph
Ph
Ph
Ph
Ph
Me
Ph
OMe
O
N
O
N
O
N
O
N
O
N
101 110 111
109
104
Entry Oxazoline R Nu Diene † (SM) / % Reaction colour*
a 101a H i-Pr 59-70 (4) dark green
b 101a H s-Bu 76-81 ‡ (1) dark green
c 101b OMe i-Pr 58-70 (3) dark green
d 109a H s-Bu 0 (95)
electric blue,
disappears
e 109b OMe s-Bu