Chrysene derivatives

Probably, the experimental conditions (temperature and solvent) determine the conversions of 2-benzopyrylium salts 266 into the chrysene derivatives 270 via a-1 dimerization or [4 + 2] cycloaddition (Scheme 14) (89TH2). 

Acid-catalysed rearrangement/hydrolysis of the 3a,20a-disulphate (168) gave the 17/3-methyl-18-nor-compound (169). Rearrangement of the 17a-hydroxy-3-oxo-A -triene (170) to the c-ring aromatic compound (171) occurred in formic acid as did the rearrangement of 17a-ethynyloestradiol to the chrysene derivative (172). The 9,ll-epoxy-17-hydroxy-steroids (173) and (174) were converted with BF3-Et20 into the C-ring aromatic compounds (175) and (176) respectively. " Normal acetonide formation in the reaction of... 

Syntheses have been reported for the chrysene derivatives (319) and (320) and it was reported that they exhibited little oestrogenic activity compared with 9a-methyloestradiol. The syntheses of the anti-tumour nitrosourea steroids (321) and (322) involved " the reaction of the respective corresponding 17a-amino-methyl and 17/3-amino-compounds with AT-alkyl-AT-nitrosocarbamoyl azide. Syntheses have been reported for the amino-oestratrienes (323) and (324). "... 

An interesting carbene-alkyne intermediate was postulated for the conversion of carbene complexes to chrysene derivatives, which again illustrates the potential of cr,Tr-activation of bridging ligands by metal centers [Eq. (32)] (225). The thermal decomposition of the carbene complex Cr-... 

C(OMe)C6H4-o-C=CPh (CO)j leads directly to the formation of a chrysene derivative via the formal dimerization of the carbene ligand. A plausible explanation for the formation of the final product involves a doubly alkyne-bridged dinuclear complex, alkyne insertions into metal-carbene bonds, and coupling of the carbene carbons. 

Wilds, A. L., Djerassi, C. Dienone-phenol rearrangement applied to chrysene derivatives. The synthesis of 3-hydroxy-1-methylchrysene and related compounds. J. Am. Chem. Soc. 1946, 68, 1715-1719. 

Polycyclic aromatic hydrocarbons are also known to undergo ort/zo-photocycloaddi-tions.805 For example, the reaction of the chrysene derivative 204 with the electron-deficient methyl cinnamate 205 affords the adduct 206 as the major product (Scheme 6.82).821 The high stereoselectivity observed has been explained by the formation of an electronically favourable sandwich-type singlet exciplex 207. 

Greiner A.C., Spyckerelle C., Albrecht P. (1976) Aromatic hydrocarbons from geological sources-I. New naturally occurring phenanthrene and chrysene derivatives. Tetrahedron 32, 257—60. 

Fig. 42. H NMR chemical shifts for carboxonium ions from chrysene derivatives (partial A5 H in parentheses).

The carbene complexes M(CO)5 =C(OMe)C6H4feCPh (M = Cr, W) undergo photodecarbonylation and alkyne coordination to form complex 56. The corresponding molybdenum complex undergoes the same reaction in the dark. The chromium species rearranges thermally to form an organic chrysene derivative. s... 

Total syntheses of steroid compounds from AD fragments can be divided into three main groups. The first of them comprises the reductive dimerization of cinnamic or phenylpropionic acid with subsequent cycliza-tion of the AD fragments obtained into chrysene derivatives (Scheme 52). 

Das A, Liao H-K, Liu R-S (2007) Platinum-catalyzed chemoselectively hydrative dimerization of 2-alkynyl-l-acetylbenzenes for one-pot facile synthesis of chrysene derivatives. J Org Chem 72 9214-9218... 

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