With no explanation, label each line with "O", "other-chemicalthing", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Unlike
the
Wittig
reaction
,
the
Petasis
reagent
can
react
with
a
wide
range
of
aldehydes
,
ketones
and
esters
.
Unlike:O
the:O
Wittig:other-chemicalthing
reaction:other-chemicalthing
,:O
the:O
Petasis:other-chemicalthing
reagent:other-chemicalthing
can:O
react:O
with:O
a:O
wide:O
range:O
of:O
aldehydes:other-chemicalthing
,:O
ketones:other-chemicalthing
and:O
esters:other-chemicalthing
.:O