Book contents
- Frontmatter
- Contents
- Authors' preface
- Abbreviations employed in this book
- Part 1 CHEMISTRY
- 1 Synthetic routes from benzenes and naphthalenes
- 2 Synthetic routes from anthracenes (A-ring formation)
- 3 Synthetic routes from phenanthrenes (D-ring formation)
- 4 Synthetic Diels–Alder routes to rings B and C
- 5 Miscellaneous synthetic routes
- 6 Tables
- 7 References to Part 1
- Part 2 BIOLOGY
- Index to Parts 1 and 2
4 - Synthetic Diels–Alder routes to rings B and C
Published online by Cambridge University Press: 07 September 2010
- Frontmatter
- Contents
- Authors' preface
- Abbreviations employed in this book
- Part 1 CHEMISTRY
- 1 Synthetic routes from benzenes and naphthalenes
- 2 Synthetic routes from anthracenes (A-ring formation)
- 3 Synthetic routes from phenanthrenes (D-ring formation)
- 4 Synthetic Diels–Alder routes to rings B and C
- 5 Miscellaneous synthetic routes
- 6 Tables
- 7 References to Part 1
- Part 2 BIOLOGY
- Index to Parts 1 and 2
Summary
Additions to 1,4-naphthoquinones
1-Vinylcyclohexene, 195, has been reacted with 1,4-naphtho-quinone, 196, to give 1,2,3,4,6,6a,12a,12b-octahydroBAQ, 197, in high yield (Backer and Bij, 1943; Azerbaev, 1945), Scheme XXIV. On air oxidation 197 was converted into 1,2,3,4-tetrahydroBAQ, 198 (Fieser and Hershberg, 1937b), which was reduced to 1,2,3,4-tetrahydroBA. With the exception of two other examples (Inbasekaran et al., 1980; Carothers and Coffman, 1932), no further work with the use of vinylcyclohexenes in BA synthesis has been reported.
Rather, the addition of styrenes, 199, to 196, has been studied and well developed. When the reactions were carried out in refluxing toluene containing chloranil and trichloroacetic acid, the following nine BAQs, 200, were obtained:4-Br-, 1-, 2-, 3-, 4-Cl-, 4-F-, 4-methoxy-, 2-methyl-, and 1,4-dimethyl- (Manning et al., 1977). Subsequently, 3,4-dimethoxy- BAQ, 201, was synthesized (Manning and Wilbur, 1980) by a similar route. When 5-hydroxy-1,4-naphthoquinone, 202, and 5-methoxy-1,4- naphthoquinone, 203, were used, mixtures of 8-hydroxy- and 11-hydroxyBAQs, 204 and 206, and 8-methoxy- and 11-methoxyBAQs, 205 and 207, resulted (Manning, 1979). By the use of 6-hydroxy- and 6-methoxy-1,4-naphthoquinones, 208 and 209, there were obtained mixtures of 9-hydroxy- and 10-hydroxyBAQs, 210 and 212, and 9-methoxy- and 10-methoxyBAQs, 211 and 213, respectively (Manning, 1979; Manning et al., 1979; Manning, 1981). The conversion of many of the BAQs into BAs and 7,12-DMBAs by conventional methods has been described (Muschik et al., 1979). However, difficulties were encountered in the synthesis of BAs bearing the 1-methoxy group because of steric factors.
- Type
- Chapter
- Information
- The Chemistry and Biology of Benz[a]anthracenes , pp. 31 - 36Publisher: Cambridge University PressPrint publication year: 1988