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Narcissus and Daffodil

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310 V.N. Bulavka <strong>and</strong> O.N. Tolkachev<br />

(40%), together with the debrominated spiro-dienone 35 (0.4%). Ketone (±)-34, on<br />

LiAlH4 reduction, produced a mixture of (±)-1 (50%) <strong>and</strong> (±)-4 (40%), which were<br />

separated chromatographically. Thus, the total yield in the synthesis of (±)-1 as<br />

shown in Figure 12.4 was 9.4%. The use of the amide synthone 33 was successful in<br />

the oxidation reaction. The yield from cyclocondensation at this step was 29 times<br />

higher than in case of tertiary amine oxidation used in Barton <strong>and</strong> Kirby’s scheme.<br />

However, taking into consideration that from the starting material 10 (not a com-<br />

7<br />

CHO<br />

OCH Ph<br />

2<br />

CHO<br />

N<br />

36 10<br />

MeO OMe<br />

MeO OH<br />

MeO<br />

Br<br />

37<br />

CN<br />

+7<br />

CO H<br />

2<br />

38 18 12<br />

MeO<br />

OCH Ph<br />

2<br />

OCH Ph<br />

2<br />

OCH Ph<br />

2<br />

CHO CHO<br />

CHO<br />

Br<br />

OH MeO<br />

39 29<br />

OCH Ph<br />

2<br />

CHO<br />

OCH Ph<br />

2<br />

Figure 12.5 Synthesis of 4-benzyloxyphenylacetic acid (10) (above; Vaghani <strong>and</strong> Merchant,<br />

1961) <strong>and</strong> of 2-bromo-4-methoxy-5-benzyloxy-benzaldehyde (29)<br />

(below; see references in text).

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