| Title:  Dihydroactinidiolide CAS Registry Number:  15356-74-8 CAS Name:  5,6,7,7a-Tetrahydro-4,4,7a-trimethyl-2(4H)-benzofuranone Additional Names:  2-oxo-4,4,7a-trimethyl-2,4,5,6,6,7a-hexahydrobenzofuran;  (2,6,6-trimethyl-2-hydroxycyclohexylidene)acetic acid lactone Molecular Formula:  C11H16O2 Molecular Weight:  180.24 Percent Composition:  C 73.30%, H 8.95%, O 17.75% Literature References:  Found in many plant sources including tea and tobacco.  (-)-Form is naturally occurring.  Produced by photo-oxidation of carotenoid flavor compounds.  Pheromone component for queen recognition in red fire ants.  Isoln from black tea aroma:  J. Bricout et al., Helv. Chim. Acta 50, 1517 (1967); from Actinidia polygama Miq. and structure determn:  T. Sakan et al., Tetrahedron Lett. 8, 1623 (1967); from tobacco and synthesis:  W. C. Bailey, Jr. et al., J. Org. Chem. 33, 2819 (1968).  Synthesis:  S. Isoe et al., Tetrahedron Lett. 9, 5561 (1968); by photo-oxidation of b-carotene:  eidem, ibid. 10, 279 (1969).  Abs config study:  eidem, ibid. 13, 2517 (1972).  Prepn of enantiomers:  K. Mori, Y. Nakazono, Tetrahedron 42, 283 (1986).  Improved prepns:  G. V. Subbaraju et al., Tetrahedron Lett. 32, 4871 (1991); A. Bosser et al., Biotechnol. Prog. 11, 689 (1995).  Prepn of (R)-form:  S. Yao et al., J. Org. Chem. 63, 118 (1998).  Germination inhibition in wheat grains:  T. Kato et al., J. Agric. Food Chem. 51, 2161 (2003). Properties:  Tan oil, bp800 108-109°.  mp 42-43°.  Fruity aroma.  uv max:  241 nm (e 10000). Melting point:  mp 42-43° Boiling point:  bp800 108-109° Absorption maximum:  uv max:  241 nm (e 10000)   Derivative Type:  (R)-Form  CAS Registry Number:  17092-92-1 Properties:  mp 70-71°.  [a]D24 -121.0° (c = 1.05 in CHCl3). Melting point:  mp 70-71° Optical Rotation:  [a]D24 -121.0° (c = 1.05 in CHCl3)   Derivative Type:  (S)-Form  CAS Registry Number:  81800-41-1 Properties:  mp 67-68°.  [a]D23 +120.9° (c = 1.00 in CHCl3). Melting point:  mp 67-68° Optical Rotation:  [a]D23 +120.9° (c = 1.00 in CHCl3)   Use:  Flavor ingredient; inhibitor of seed germination.  |