摘要:

Org. 1997 Overcrowded Molecules. Part V1.l Photocyclisation of cis-ga,I O-Di- hyd ro-9-methyl-10,I 5-d iphenyl-9H- benzo[5,6] indeno [2,1 -c] phen- anthrene By H. G. Heller * and K. Salisbury, Edward Davies Chemical Laboratory, University College of Wales, Aberyst- wyth D i p h e n y I ke t e n re a c t s with (E ) - 2 - b en z y I id e n e - 2,3 - d i h y d r o - 3 - met h y I - 2,3 - d i h y d roc y c I o p e n t a [ c] p h en ant h re n e - 1 -one at 180" to yield cis-9a.l O-dihydro-9-methyl-10,I 5-diphenyl-W-benz[5,6] indenol2.1 -c]phenanthrene having an anti-arrangement of methyl and 1 O-phenyl groups. This overcrowded hydrocarbon undergoes photo- cyclisation by the less hindered of the two allowed controtatory processes to give 5a.6.1 Ob,l3e-tetrahydro- 5 - met h y I - 6, I 0 b - dip h e n y I - 5H- c yc I o p e n ta [ def] nap h t h o [ 8,1,2 -pqr] c h ry se n e h avi n g a cis- arrange m e n t of 5 a -, 6 -, and 13e-hydrogens and the methyl group anti to both phenyl groups.1 ,2-BlSDIPHENYLMETHYLENE-3-METHYLINDANE (1) under- goes photochemical electrocyclic ring closure followed by a 1 ,&hydrogen shift to yield 4b,5-dihydro-l l-methyl- 5,5,10-tripheny1-11H-benzo[b]fluorene (2) having the methyl group anti to the 4b-hydrogen, indicating that $Ph2 E steric effects determine which of the allowed conrotatory processes 0ccur.l A Dreiding model of 1,2-bisdiphenyl- methylene-2,3-dihydro-3-met h yl-1H-cyclopent a[c] phen- anthrene (7) showed that an analogous photoreaction could not occur for this diene because of the severe steric interactions either between phenyl group D and the phenanthrene nucleus or between phenyl groups B and c, depending on the direction of rotation about the l-di- phenylmethylene group, and that its photorearrangement should be of interest. Unfortunately, diene (7) could not be synthesised in the usual manner by the reaction of diphenylketen with the corresponding ketone (5).Related studies are reported which show that photo- cyclisation of hydrocarbon (9) occurs in accord with the Woodward-Hoffmann rules by the less hindered of the two allowed controtatory processes, and indicate that it appears immaterial here as in other cases l y 3 y 4 whether the open-chain valence isomer incorporates the x-elec- trons of the aromatic system or not. (E)-Z-Benzylidene-Z,3-dihydro-3-methylcyclopent a[c]- phenanthren-l-one (3) reacts with diphenylketen at 180" to yield cis-9a,lO-dihydro-9-methyl-10,15-diphenyl-9H- benzo [5, 6lindeno [2 , 1 -c] phenanthrene (9) with an anti- 1 Part V, H.G. Heller and I<. Salisbury, J . Chem. Soc. ( C ) , 1970, 873. a R. Hoffmann and R. B. Woodward, Accounts Chem. Res., 1968, 1, 17; The Conservation of Orbital Symmetry, Academic Press, 1970. 3 H. G. Heller and K. Salisbury, J . Chem. SOC. ( C ) , 1970, 399. arrangement of methyl and 10-phenyl groups. Its stereochemistry follows from its n.m.r. spectrum [T 8-55 (d, J9a,10 7 Hz, Me)] which resembles closely that of hydrocarbon (10) [T 8.6 (d, J1O,lOa 8 Hz, Me)] and not that of hydrocarbon (11) [T 9.2 (d, J1O,lOa 16 Hz, Me)].3 A Dreiding model of hydrocarbon (9) shows that the 15-phenyl group overlaps the phenanthrene nucleus on the same side as the 10-phenyl group.The reaction of ketone (3) with diphenylketen is considered to give the thermally unstable p-lactone which eliminates carbon dioxide and either undergoes cyclisation before n-bond formation can occur,6 or relaxes to diene (8) which, under the reaction conditions, undergoes thermal ring closure followed by a 1,5-hydrogen shift. Hydrocarbon (9) in light petroleum, on exposure to 366 nm radiation, rearranges to only one of the four possible isomers of 5a,6,lOb,13e-tetrahydro-5-methyl- 6,l0b-diphenyl-5H-cyclopenta[def]naphtho[8,1,2-~qr]- chrysene (12), m.p. 264-265". Because of the estab- lished stereochemistry of compound (9), hydrocarbon (12) must have a syn-arrangement of 5a- and 6-hydrogens and the methyl group anti to the 6-phenyl group.Ring closure by disrotatory mode a or conrotatory mode b would involve severe steric interactions between the 15-phenyl group and the phenanthrene nucleus, and need not be considered further. Ring closure by conrotatory mode c or disrotatory mode d gives rise to the cis- and trauts-5a,l3e-dihydro-isomers (12a) and (12b) respectively. A Dreiding model of isomer (12a) shows that the phenan- threne and benzene rings lie essentially in one plane with the 10- and ll-hydrogens in close proximity and in the deshielding regions of the aromatic rings and that it is therefore to be expected that in this isomer the 10- and ll-hydrogens would appear at low field in the n.m.r.spectrum (cf. the n.m.r. spectrum of benzo[c]phenan- threne which shows absorptions due to the 1- and 12-hydrogens centred at 7: 0-85).6 A Dreiding model of isomer (12b) shows a strained folded structure with the 10- and ll-hydrogens out of the plane and not in the G. Quinkert, K. Opitz, W-W. Wiersdorff, and M. Finke, Annalen, 1966, 693, 44; 0. L. Chapman and G. L. Eian, J . Amer. Chem. SOL, 1968, 90, 5329; R. J. Hart, H. G. Heller, and K. Salisbury, Chern. Cornrn., 1968, 1627. H. G. Heller and K. Salisbury, Tetrahedron Letters, 1968, 2033. 6 R. H. Martin, N. Defay, and F. Geerts-Evrard, Tetrahedron, 1965, 21, 2421.1998 J. Chem. SOC. (C), 1970 deshielding region of the aromatic rings to which they are not attached. The n.m.r. spectrum of hydrocarbon (12) shows marked deshielding of the 10- and ll-hydro- gens, which give rise to quartets centred at T 1.14 and 1.57, indicating that the hydrocarbon is the cis-isomer (12a).The high-field aromatic absorptions (z 3.25- 3-85) are assigned to the hydrogens of each syn-phenyl group shielded by the adjacent parallel benzene ring (cf. aromatic hydrogens of [2,2]paracyclophane (7 3-64),' and the phenyl hydrogens of 1,s-diphenylnaphthalene (z 3-15) 8>. The splitting pattern of the methine protons and double resonance studies are consistent with the proposed structure (12a). methylpyridine, yielded ketone (5) and 2-diphenyl- methyl-3-met hyl-1H-cyclopent a [c] phenant hren-1 -one (6), separated by chromatography on alumina. EXPERIMENTAL N.m.r. spectra were obtained for solutions in deuterio- chloroform, for compounds (4; R = H), (9), and (12a) with a Varian HA-100 (100 MHz) spectrometer, and others with Perkin-Elmer R10 or R12 (60 MHz) spectrometers.U.V. spectra were measured for solutions in chloroform [except for hydrocarbons (9) and (12a) which were studied in n- hexane] with a Unicam SP 500 spectrometer). Chroma- tography was carried out with Spence type H alumina. 2-(3-Phenanthryl)butyric acid,g was converted into 2,3-dihydro-3-methyl-lH-cyclopenta[c] phenanthren- l-one by the action of polyphosphoric acid at 100" lo and condensed with benzaldehyde in the presence of 10% ethanolic potassium hydroxide to give ketone (3). Re- action of bromide in chloroform with 2-diplienylmethyl- 2,3-dihydr0-3-methyl-l H-cyclopent a[c] phenant hren- l-one (4; R = H), prepared by the reaction of phenyl- magnesium bromide on ketone (3), gave the 2-bromo- derivative (4; R = Br) which, when boiled with 2,4,6-tri- 7 D.J. Cram, C. K. Dalton, and G. R. Knox, J . Amer. Chem. 8 H. 0. House, R. W. Magin, and H. W. Thompson, J . Urg. SOC., 1963, 85, 1088. Chem., 1963, 28, 2403. 2 , 3-Dihydro-3-~nethyl- lH-cyclopenta[c]Phenanthren- 1-one. -2-(3-Phenanthryl)butyric acid (5.0 g.) was stirred (3 h) in polyphosphoric acid (180 g) a t 100°.lo Work-up gave an oily solid (4 g) which was dissolved in light petroleum and kept a t 0" for several days. The dihydro-3-~nethylcyclofienta- phenanthren-l-one (2.8 g) crystallised out, m.p. 138-140" (from light petroleum) (Found : C, 86.75 ; H, 5.85. Cl,H,,O requires C, 86-85; H, 5.75%); vmx.1710s cm-l ( G O ) . 2-Benzylidene-2,3-dihydro-3-methylcyclopenta[c]phenan- thren-l-one (3) .-The foregoing ketone (2.0 g) and benzalde- hyde (1.0 g) in ethanol (30 inl) was treated with 10% ethanolic potassium hydroxide (3 ml) while the temperature W. E. Bachmann and J. M. Chemerda, J . Org. Chem., l o B. R. T. Keene and K. Schofield, J. Chem. SOC., 1958, 1080. 1941, 6, 36.Org. 1999 of the mixture was maintained a t 40" for 30 min. The benzylidene derivative (3) (2.4 g) separated from the cooled mixture, m.p. 181" (from acetic acid) (Found: C, 89.85; H, 5.45. C25H180 requires C, 89.8; H, 5.4%); v,, 1682s \ cis \ cm-l ( G O ) ; T 0.01 (lH, m, 11-H), 1*88-2.80 (13H, com- plex m, olefinic and aromatic H), 5.56 (lH, q, J 7 Hz, 3-H), and 8.53 (3H, d, J 7 Hz, Me).2-Di~henylmethyZ-2,3-dihydro-3-methyZcyclo~enta[c]phen- anthren-1-one (4; R = H).-The benzylidene ketone (3) (3.6 g) in benzene (160 ml) was added to a solution of phenylmagnesium bromide, prepared from bromobenzene (5.0 g) and magnesium (0.8 g) in ether (120 ml), and the mixture was boiled (1 h) and worked-up. The diphenyl- methyl ketone (4; R = H) (3.5 g) had m.p. 169-170" (from ethanol) (Found: C, 89.65; H, 6.0. C,,H,,O requires C, 90.2; H, 5.85%) ; v,, 1710s cm-1 (GO) ; 294 and 319 nm (log E 4.56 and 3.80); T 0.90 (lH, d, J 8 Hz, 11-H), 1.92-2-284 (17H, complex m, ArH), 5.50 (lH, d, J 9 Hz, Ph,CH), 6.70 (2H, q, J 8 Hz, 2- and 3-H, magnetically equivalent), and 8.71 (3H, d, J 8 Hz, Me). Irradiation a t T 6-70 caused the Me and the Ph,CH signals to become singlets.2-Bromo-2-dil>henylmethyZ-2, 3-dihydro- 3-methylcyclopenta- [c]phenanthren-I-one (4; R = Br).-Bromine (0.63 g) in chloroform (15 ml) was added to the diphenylmethyl ketone (4; R == H) (1.6 g) in chloroform (30 ml) at 40", and the mixture was heated (3 h) at 50". Removal of the solvent followed by trituration of the resulting oil with ethanol gave the unstable 2-bromo-derivative (4; R = Br) (1.7 g), m.p. 295-296' (decomp.) (from acetic acid); v- 1710s cm-l (GO); Am= 288 and 330 nm (log E 4-22 and 3.65); T 0.74 (lH, m, 11-H), 1*78-3.02 (17H, complex m, ArH), 4.70 (lH, s, Ph,CH), 5-84 (lH, q, J 7 Hz, 3-H), and 8.54 (3H, d, J 7 Hz, Me). 2-Diphenylmethyl-3-methyL 1H-cycZopenta[c]$henanthren- 1-one (6) and 2-Diphenylmethylene-2,3-dihydr0-3-methyl-lH- cycZoPenta[c]~henuathren-1-one ( 5 ) .-A solution of the bromo- ketone (4; R = Br) (2.0 g) in 2,4,6-triniethylpyridine (12 ml) was boiled (3 h) .The cooled mixture was treated with ice and dilute hydrochloric acid and filtered. The residue in benzene was chromatographed on alumina. Elution with light petroleum of the first orange band gave the 2-diphenyZmethyl-3-methylcyclo~ent~~henanthren-l-one (6) (0-8 g, 49y0), red crystals, m,p. 152" (from acetic acid) (Found: C, 90.8; H, 5-45. C31H220 requires C, 90.7; H, 5.4%); vmax 1695s cm-l ( G O ) ; Lk 304 and 316 nm (log E 4.33 and 4.38); z 0.00 (lH, m, 11-H), 2.08-2.80 (17H, complex m, ArH), 4.35 (lH, s, :CH*), and 8.15 (3H, s, Me). The second yellow band gave the Z-diphenylmethylene- 2,3-dihydro-3-methylcyclo~enta~henanthren-l-one ( 5 ) (0.6 g, 3Gy0), bright yellow crystals, m.p.277-279" (from acetic acid) (Found: C, 90.4; H, 5.4. C,,H,,O requires C, 90.7; H, 5.4%) ; v,, 1680s cm-l ( G O ) ; a,, 289,340, and 348 nm (log E 4-35, 4-28, and 4-26) ; T 0.45 (lH, m, 11-H), 1.87-2.78 (17H, complex m, ArH), 5-55 (lH, q, J 7 Hz, 3-H), and 8-85 (3H, d, J 7 Hz, Me). Reaction of Diphenylketen with Ketones (5) and (6j.- When ketone ( 5 ) or (6) (1 g) was heated (24 h) with diphenyl- keten (1.2 g) at 205", no carbon dioxide was evolved and, on work-up, the ketone was recovered in quantitative yield. The only product of these reactions was tetraphenylcyclo- butane-l,%dione, m.p. 249", identified by mixed m.p. with an authentic sample. The lack of reaction is attributed t o the fact that the carbonyl groups of the ketones are sterically hindered.Reaction of Diphenylketen with the Be.itzzylidene Ketone (3). -An intimate mixture of diphenylketen (1.3 g ) and ketone (3) (2.0 g) was heated ( 5 h) a t 180" under nitrogen. The resulting glass was dissolved in benzene and chromato- graphed on alumina with light petroleum as eluant. The first band gave 9a, 1 0-dilzydro-9-methyl- 10,15-di- $henyZ-9H-benz[5,6]iadeno[2, 1-c]$hePzanthrene (9) (1.5 g, 52 yo), yellow crystals with an intense green fluorescence, m.p. 231-232" (from acetic acid) (Found: C, 93.8; H, 5.9. C38H28 requires C, 94.2; H, 5.8%) ; Lx. 245, 303, 318, 360, 375, and 395 nm (log E 4.63, 4.14, 4.10, 4.10, 4.07, and 4.05); (complex m, ArH), 5.34 (lH, d, J g , l o 9.5 Hz, 10-H), 6-18 (lH, q, J9a,10 9.5 Hz, Ja,ga 7 Hz, 9a-H), 6-90 (lH, quintet, J 7 Hz, 9-H), and 8-55 (333, d, J 7 Hz, Me).* Irradiation a t T 5.34 caused the 9a-H signal to become a doublet (J 7 Hz), a t T 6.20, 10-H to become a singlet, a t z 6.90, Ba-H t o become a doublet ( J 7 Hz), and the methyl signal to become a singlet.* The second band of the column gave unchanged ketone Photorearrangement of Hydrocarbon (9) .-The hydrocarbon (9) (0.3 g) in light petroleum (600 ml) was exposed (7 days) to 366 nm radiation from a 125 W mercury-vapour lamp.The pale yellow solution turned colourless. Removal of T 1-32 (lH, 9, J O l t b 7 Hz, Jmeta 2 Hz, 1-H), 2.39-3.60 (3) (0.7 g). * Coupling constants were misquoted as haIf the actual values in the preliminary communication.s2000 J. Chem. SOC. (C), 1970 the solvent, followed by chromatography of the residual oil (0.29 g) on alumina with light petroleum as eluant, gave 5a, 6, lob, 13e-tetrahydro-5-methyl-6, 1 Ob-diphenyZ-5H-cycZo- penta[deflnaptho[8, l,Z-pqr]chrysene (12a), colourless crystals with a blue fluorescence, m.p. 264-265" (from ethanol- benzene) (0.25 g, 85% yield) (Found: C, 94.05; H, 6.2. C3&8 requires C, 94.2; H, 5.8%); A,, 268, 276, and 310 nin (log E 4-34, 4.31, and 3.83); T 1.14 (lH, q, Jo 8 Hz, Jm 1 Hz, 10- or 11-H), 1.57 (lH, q, Jo 7 Hz, Jm 2 Hz, 10- or 11-H), 2-28-2-90 and 3.25-3.85 (21H, complex m, ArH), 5.02 (lH, d, J 11-6 Hz, 6- or 13e-H), 5.59 (lH, d, J 12.6 Hz, 6- or 13e-H), 6-00 (lH, quintet, J 8 Hz, 5-H), 6.52 (lH, m, 5a-H), and 8-14 (3H, d, J 8 Hz, Me). Irradiation at ?: 5.02 caused the 5a-H signal to become a quartet (J5,5a 8 Hz and J6a,6 or J5B,13e 12.6 Hz), irradiation a t ?: 6.52 caused the 6-H and 13e-H signals to become singlets, irradiation at 7: 6-00 caused the methyl signal to become a singlet, and irradiation a t -r 8.14 caused the 5-H signal to become a doublet ( J 8 Hz).* [9/2117 Received, December llth, 19691 * Coupling constants were misquoted as half the actual values in the preliminary communication. 5

ISSN:0022-4952    

DOI:10.1039/J39700001997

出版商:RSC    

年代:1970

数据来源: RSC