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Functionalized Enantiomerically Pure [2.1.1]- [2.2.1]- and [2.2

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shifted in the direction of the nitrogen atoms of the neighboring layer.
Since the phase transformation takes place at the relatively low pressure of 0.6 GPa, it can hardly be ruled out
that at least a partial transformation of a-Li3N into B-Li,N
takes place on preparing powdered samples by grinding in
a mortar, so that X-ray powder photographs of a-Li3N always show small amounts of B-Li3N. The observation of
"additional reflections" in Li3N powders was first reported in the literature more than a decade ago.["]
Depressurized Li3N samples which had previously been
subjected to pressures of more than 10 GPa were investigated by the Gandolfi
In one case an X-ray
powder diagram was obtained whose reflections were consistent with a cubic structure with extinctions corresponding to an F-centered lattice (observed reflections 11 I , 200,
220, 31 1; a=427.3(2) pm; CuKa radiation). It is assumed
that the highest pressure phase of Li3N crystallizes in the
Li,Bi-type ~tructure."~'
Dimorphism between Na3As- and
Li,Bi-type structures is also observed in some higher
homologues of Li3N, e.g. in K3BiiI4]and Li3Sb.[l3I
Received: March 22, 1988 [Z 2672 IE]
German version: Angew. Chem. 100 (1988) I I16
[ I ] A. Rabenau, Fesrkorperprobleme I8 (1978) 77.
121 A. Rabenau, Solid State Ionics 6 (1982) 24.
131 M. Mali, J. Roos, D. Brinkmann, Phys. Rev. 8: Condens. Matter 36
(1987) 3888.
[4] E. Schonherr, G. Miiller, E. Winkler, J . Crysf. Growth 43 (1978) 469.
[S] A. Jayaraman, Reu. Mod. Phys. 55 (1983) 65.
161 G. J. Piermarini, S . Block, J. D. Barnett, R. A. Forman, J . Appl. Phys. 46
(1975) 2774.
(71 D. Louer (Laboratoire de Cristallochimie, Universite des Rennes I ) :
DICVOL, Trial and Error Method f o r the Automatic Indexing of Powder
Patterns, 1982.
[8] G. Brauer, E. Zintl, 2. Phys. Chem. Abr. 8 3 7 (1937) 323.
(91 K. Yvon, W. Jeitschko, E. Parthe (Laboratoire de Cristallographie aux
Rayons-X, Universite de Geneve): LAZY-PULVERIX, A Program ro calculate X-Ray and Neutron-Dffracrion Powder Patterns, 1977.
[lo] A. Rabenau, H. Schulz, J. Less-Common Met. SO (1976) 155.
[ I I ] B. A. Boukamp, R. A. Huggins, Phys. Lett. A S 8 (1976) 231.
[I21 G . Gandolfi, Mineral. Perrogr. Acta 13 (1967) 67.
(131 E. Zintl, G. Brauer, 2. Elektrochem. Angew. Phys. Chem. 41 (1935) 297.
1141 D. E. Sands, D. H. Wood, W. J. Ramsey, Acta Crystallogr. 16 (1963)
316.
Functionalized, Enantiomerically Pure
12.1.11-, 12.2.1]-, and I2.2.21-Triblattanes**
By Hermann Muller, Johann-Peter Melder,
Wolf Dieter Fessner. Dieter Hunkler, Hans Fritz,
and Horst Prinzbach*
1 should prove useful as starting material include not only
the already known D,-symmetric 1,4,7-trisexomethyleneand 1,4,7-trispiro-deri~atives['~
and 1,4,7-tris~arbocations,~~~
but also variously functionalized as well as variously (hetero)benzoid annelated [2.1.1]- (A), [2.2.1]- (B) and [2.2.2]triblattanes ( C).[3,41
Such structural entities are of interest,
A
8
C
inter alia, as synthetic intermediates for the study of intramolecular interaction^^^] between their characteristically
oriented X = Y chromophores, because of their chiroptic
properties,13] and because of their potential as "chiralica".
Herein we present efficient methods for the synthesis of
the prototypical, enantiomerically pure structural entities
A, B and C with homonuclear X=Y units (HC=CH,
C6H4). Their PE, O R D and X-ray structure analyses,'61
preparative extensions (e.g. to X = Y = C-N; R = C 0 2 H ,
NHJ, and preparative/analytical applications will be reported elsewhere.i71
For the synthesis of the C,-symmetrical dimethanotwistene rac-8 from the [l.l.l]-ketone rac-2l8] (Scheme I), several standard methods of homologization and olefination
were tested regarding the problems of twofold and threefold functionalization of 10 and 1 , respectively. The ring
enlargement of 2 to the [2.1.1]-ketone 5 (according to Nakazaki et al. less selective (56%) with CH,N2131)was accomplished in 75-80% yield, both according to the method of
Schollkopf et al.I9] as well as with a modified fifleneauDemjanov method (2-3-4-5,
82%).1'*.1'1Several variants of p-elimination for the olefination at the stage of
the alcohols (e.g. - H 2 0 , -HOAc, -HOMes) derived
2
3
4
6
7
-101/-160( IS)
l+lOl/+l6O~lR~l
We have developed an efficient scheme for the synthesis
and resolution of the gyrochiral, D3-symmetric trishomocubanetrione 1.[I1 Target compounds for which compound
5
-219/-377(1/7)
1+221/+381 (IS)
(-1- 1
(*)-l
__c
5
['I Prof. Dr. H. Prinzbach, Dip].-Chem. H. Miiller,
[**I
DipLChem. JLP. Melder, Dr. W:D. Fessner, Dr. D. Hunkler,
Prof. Dr. H. Fritz
Chemisches Laboratorium der Universitat,
Institut fur Organische Chemie und Biochemie
Albertstr. 21, D-7800 Freiburg (FRG)
This work was supported by the Deutsche Forschungsgemeinschaft, the
Fonds der Chemischen Industrie, and BASF AG.
Angm.. Chem. Int. Ed. Engl. 27 11988) No. 8
@
I
0
6
a
9
-210/-332 (1R)
1+210/+332(
IS)]
-279/-447( IS)
1+282/+451(1R)]
Scheme 1. The numbers quoted here and in the other schemes refer to specific rotations of the pure enantiomers measured at ,
I
= 587 nm in cyclohexane o r chloroform, respectively (10, 17).
0 VCH Verlagsgesellschaft mbH. 0.6940 Weinheim. 1988
OS70-0833/88/0808-1103 $ 02 SO/O
1 I03
from the ketone 5 proved to be unproductive (the same
holds true for attempts with the diols and triols derived
from the diketone 12 and the triketone 16, respectively).
We therefore attempted olefination according to the methods of Barnford, Stevens and Shapiro, of Fetizon et al.,["]
and of Perkow and Biunchini et al.[l3I The 'H- and "CNMR spectra of the waxy solid substance rac-8 (rucpentacyclo[6.4.0.026.03.10.05~9]dodec-1
1-ene, A,, (cyclohexane) = 210 nm ( E = 1220))["], isolated according to the last
method in 80-85% yield (based on 5 ) , showed the expected
seven and six signals, respectively, for C2-symmetry (Table
1). The enantiomers of 2, separated by the method of
Euton and Leip~ig,"~]
analogously furnished (+)-8 and
( - )-8, thus also establishing their absolute configuration.
Hydrogenation of ( + ) - 8 and (-)-8 yielded enantiomerically pure (+)- and (-)-[2.1.l]-triblattane 9, respectively;
(-)-9 has already been described as an optically enriched
sample.[']
Because of the relatively rapid formation of higher triblattanes,I3I the CH2N,-variant was a priori not taken into
consideration for the single ring enlargement of the two
cyclopentanone rings in the [I.l.l]-diketone rac-lO["]
which was required on the route to the C2-symmetric
methanoditwistadiene ruc-14. Via the intermediates isolated anaIogously to 314 (reaction steps a and b in Scheme
2) in test runs,["] an impressive yield of 75% of a mixture of the three [2.2.1]-diketones 11 ( C 2 ;ruc-pentacyc10[7.4.0~~~.0~~".O~~'~]trideca-7,12-dione),
12 (C2; -8,13-dione) and 13 ( C , ; -7,13-dione) was achieved. Pure 11 (m.p.
175-176"C, 18-20%) could be isolated from the product
'b
11(12,13)
10
+300/+522(1R)
I-300/-522(1S11
Table I. Melting points, 'H-NMR spectra (CDCI,, 400 MHz) and "C-NMR
spectra (CDCI,, 100.6 MHz) of selected compounds.
f
/
-264/-535( IS)
[+257/+520( 1 R ) I
8 : m.p. 84-86°C; 'H-NMR (250 MHz): 6=6.14 (m, 11.. 12-H), 2.20-2.25 (m,
1-, 10-H; m, 3-, 8-H), 1.68 (m, 5-, 6-H), 1.56 (m. 2-, 9-H), 1.48 and 1.28 (AB,
4,4-, 7,7-H2); "C-NMR: 6=130.2 (C-11, -12), 50.1 (C-1, -lo), 47.3 (C-5, -6),
44.2 (C-3, -8), 36.1 (C-2, -9), 33.6 (C-4, -7)
14: m.p. 47-48°C; 'H-NMR (250 MHz): 6=6.35 (ddd, 8-, 13-H), 6.07 (ddd,
7 - , 12-H), 2.44 (t, 6-, 11-H), 1.90 (m, 3-, 5-H), 1.80 (t. I-, 9-H), 1.56 (br. s,
4,4-H2), 1.34(br. q. 2-, 10-H); "C-NMR:6= 133.8 (C-8, -13), 129.1 (C-7, -l2),
48.2 (C-3, -5). 46.9 (C-6, - l l ) , 45.1 (C-1, -9), 36.2 (C-4), 29.5 (C-2, -10)
18: m.p. 106-107°C; 'H-NMR (250 MHz): 6=6.42 (m. 6 H , H,,,,), 1.97 (m,
6 H , HSllph).
0.95 (br. q, 2 H , 2-, 11-H); "C-NMR: 6 = 134.3 (6C), 47.1 (6C),
20.8 (2C)
21: 'H-NMR: 6=3.31 (t, 4-, 8-, 14-H), 3.20 (t, 5-, 9-, 13-H), 2.83 (br. t, I-, 3-,
7-H), 2.18 (m, 6-, lo-, 11-, 12-H), 1.97 (br. q, 2-H); "C-NMR: 6=54.6 (C-4,
-8, -14), 48.6 (C-5, -9, -l3), 36.0 (C-6, -10, -l2), 33.0 (C-2), 29.9 (C-ll), 29.7
(C-1, -3, -7)
2 2 : m.p. 189-190°C; 'H-NMR (250 MHz): 6=3.46 (I, 1 H), 3.42 (t. 1 H), 3.28
(t, 1 H), 3.24 (t. I H), 3.12 (br. t, 2H), 3.03 (br. t, 1 H), 2.98 (br. t, 1 H), 2.90 (br.
t, IH), 1.99-2.15 (m. 4H), 1.94(br. t, 1H); "C-NMR: 6=54.5, 54.2, 54.1,
49.5, 49.2, 49.0, 35.7, 35.4, 34.9, 31.6, 30.7, 30.6 (2C), 29.9
23: m.p. 100-101°C; 'H-NMR: 6=7.20 (m, 4H), 2.73 (d, 1-, 10-H), 2.43 (m,
5-, 6-H), 1.90 (br. q, 2-, 9-H), 1.80 (m, 3-, 8-H), 1.63 and 1.47 (AB, 4,4-, 7.7H2); "CC-NMR: 6 = 140.3 ('2-11, -l2), 125.6 (C-3', -6'*), 124.4 (C-4', -5'*), 49.6
(C-5, -6), 47.8 (C-1, -10). 46.4 (C-3, -8), 37.4 (C-2, -9), 34.0 (C-4, -7)
24: m.p. 59-60°C; 'H-NMR: 6=7.10-7.19 (m, 4H), 6.39 (br. t, 13-H), 6.18
(br. t, 12-H), 2.93 (br. d, 6-H), 2.58 (br. t, 11-H), 2.30 (d, 9-H), 2.06 (m, 3-H),
1.93 (m, 5-H), 1.80 (br. t, I-H), 1.71 and 1.65 (AB, 4,4-H2), 1.62 (m, 2.. 10-H);
"C-NMR: 6 = 143.2, 139.9 (C-7, C-8), 133.5 (C-l3), 129.7 (C-12), 125.6 (C-3',
-49, 124.8, 123.4(C-5', C-69, 50.8 (C-6), 49.1 (C-9). 48.0 (C-3), 47.4 (C-5), 46.6
(C-ll), 43.9 (C-l), 36.5 (C-4), 31.5, 30.9 (C-2, C-10)
25: m.p. 209-210°C; 'H-NMR:6=7.20(m,6H),7.08(m,2H),3.06(br.
d,6-,
11-H), 2.30 (br. d, 1-, 9-H), 2.08 (m, 3-, 5-H), 1.90 (br. q. 2-, 10-H), 1.82 (m,
4,4-H2); "C-NMR: 6=142.5, 139.8 (C-7, -12, C-8, -13), 126.0, 125.8 (C-4',
-4", C-5', -5"), 125.0 (C-6', -6"), 123.4 (C-3', -3"), 50.4 (C-6, -ll), 47.4 (C-I,
-9), 47.2 (C-3, -5), 36.9 (C-4), 32.8 (C-2, -10)
26: m.p. 91-93°C; 'H-NMR: 6=7.17 (br. s, 4H), 6.48 (td, 9-, 14-H), 6.44 (td,
8-, 13-H), 2.50 (d, 3-, 6-H), 2.12 (br. t, I-,10-H), 1.90 (br. t, 7-, 12-H), 1.27 (br.
q, 2-, 11-H); "C-NMR: 6=143.8 (C-4, -5), 134.4 (C-9, -14), 133.6 (C-8, -13),
125.3 (C-4', -5'), 123.8 (C-3', -6'), 50.4(C-3, -6), 46.7 (C-7, -l2), 45.2 (C-I, -lo),
22.8 (C-2, -1 1)
27: m.p. 178-179°C; 'H-NMR: 6=7.22 (m, 4H), 7.15 (m, 2H), 7.10 (m, 2H),
6.51 (m, 13-, 14-H), 2.63 (d, 3-, 10-H), 2.42 (d, 6-, 7-H), 2.05 (m, I-, 12-H), 1.57
(br. q, 2-, 11-H); "C-NMR: 6 = 143.5, 142.9 (C-4, -9, C-5, -8), 133.7 (C-13,
-l4), 125.7, 124.5, 125.6 (C-4', -S", C-5', -4", C-6', -3"), 123.8 (C-3', -6'9, 50.0
(C-3, -lo), 48.6 (C-6, -7), 44.9 (C-I, -l2), 24.7 (C-2, -11)
28: m.p. 215-216°C; 'H-NMR: 6=7.23 (m, 6H), 7.17 (m.6H), 2.57 (br. d,
6H), 1.90 (br. q, 2H); "C-NMR: 6= 142.7 (6 ipso-C), 125.9 (6 m-C), 124.0 (6
0-C), 48.4 (6C), 26.7 (2C)
30:m.p. >370"C; 'H-NMR: 6=8.11 (m, 6H), 7.80 (m, 6H), 3.34 (dd, 6H),
2.87 (br. q, 2H); "C-NMR: 6= 155.5 (C-4, -5, -8, -9, -13, -14), 142.2 (6 ipsoC), 129.6 (6 0-C), 129.1 (6 m-C), 47.4 (6C), 28.2 (2C)
1104
0 VCH Verlagsgesellschaft mbH, 0-6940 Weinheim, 1988
14
15
-264/-449( IS)
-415/-723(18)
[+422/+735(1R)I
1+265/t450(1R)I
Scheme 2
mixture by chromatography and pure 12 (m.p. 183-184"C,
25 "C) by crystallization. The twofold olefination also presented no problems. After extensive preliminary experimentation with pure diketone rac-11, pure tetrachloro-derivative (step d) and pure bisenol ester (step e), an average
yield of 75% of crystalline ruc-14 (rac-pentacyc10[7.4.0.0~~~.0~~'
'.05,'0]trideca-7,12-diene)
was finally achieved on using the mixture of diketones 11-13 via the Perkow route, suitably modified at the chlorination stage
(steps d-f).["l The C,-symmetry of 14 is confirmed by the
'H-/"C-NMR
spectra (Table 1, Jl,z
=Jz,3=J2,6=6.0,
33,4=1.5, 55.6z.0, J6,7=7.0, J7,8=8.0, J8,9=7.0 Hz; Amax(CYclohexane) = 21 5 nm (6= 2720)). After efficient enantiomeric separation of ruc-10 with (R,R)-2,3-butanediol,['] the
pure enantiomers (+)- and (-)- 14 could be prepared and
their absolute configuration be confirmed by hydrogenation to (+)- and (-)-15, respectively['31 (15% optically
pure (-)-15 has already been described; [a]= -58.6, calculated - 404[31).
A key role in o u r studies with the unsaturated [2.2.2]triblattanes is played by the D,-symmetrical (CH)14[161
tritwistatriene 18. The preparative demands associated therefore
with the synthesis of 18 from the [l.l.l]triketone 1 could
be largely fulfilled (Scheme 3): both the steps a-c leading
to the threefold homologization of ruc-1, which afford a
1 :2 mixture (53%) of the chromatographically separated
triketones 16 (C3; r~c-pentacyclo[8.4.0.0~~~.0~~'~.0~~'']tetradeca-4,8,14-trione, m.p. 245-247"C, 17%) and 17 ( C ,;
-4,8,13-trione, m.p. 236-237"C, 36%), as well as the steps
d-f for the threefold olefination carried out with the ketone mixture according to the Perkow method, which is the
only suitable method here, are reduced to economical onepot reactions. The latter steps had been optimized to an
overall yield of 68% using the pure triketones 16 and 17,
0570-0833i88i0808-JI04 $ 02.50iO
Angew. Chem. Inc. Ed. Engl. 27 (1988) No. 8
2
0
The C=C or C=O functions in the [2.1.1]-, [2.2.1]-, and
[2.2.2]-triblattanes presented here can be used in the usual
way for the annelation of benzoid or heterobenzoid rings.
Thus, the benzoannelated derivatives 23,24 and 25 or 2628 could be prepared in good to very good yields from the
enantiomerically pure olefins 8, 14 and 18 via the tetrachlorothiophene dioxide adducts (Table 1).
0
0
-414/-754( 1R)
-621/-1169(15)
[+410/+747(15)1
[+617/+1161(1R)I
24
23
Scheme 3
the two hexachlorotriketones (step d) and trisenol esters
(step e). The yield of crystalline ruc-lS["I (ruc-pentacy~10[8.4.0.0~~~.0~~'~.0~~~']tetradeca-4,8,13-triene,
il,,,(cyclohexane) = 216 nm (E =4240)), based on rac-1, is an impressive 36% for at least 21 functional changes. The antipodes
(+)-18 and (-)-18 obtained from the triketones (+)-1
and (-)-1 or (+)-16( 17) and (-)-16( 17), respectively,
have been correlated by hydrogenation with (+)-19 and
(-)-19, respectively, (the known (-)-19 had an optical
purity of 44%; [a]= - 250, calculated - 567[31).
The &-symmetry of 18 is confirmed by only three 'Hand 13C-NMR signals (Table 1, J1,2=7.5, J1+,=4.5 Hz).
Despite a strain energy of 49.1 kcal mol - ' (force field calculation, MM2; 45.9 (47.7) kcal mol-' for 8 (14)), 18 is
thermally very stable; it slowly changes on heating in benzene (ca. lo-' M) above 200°C; under dehydrogenating
conditions (over Pd/C), mainly phenanthrene (X =
HC=CH) (up to 75%) is formed-presumably via [4+2]cycloreversion (20, Scheme 4, cf. basketene and ansaradiene).['71In an analogous way, 14 furnishes fluorene (X =
CH2) in ca. 75% yield.
25
-162/-338( 15)
-282/-622(1R)
-261/-707( 1R)
[+164/+342( 1R)l
[+280/+617( 1 5 ) l
[+259/+701(1S)I
26
27
28
-463/-1077
-488/-1320 (1Rl
(1Rl
[+490/+ 1 325 ( 1S ) 1
[+457/+1062( 1S)I
-493/-1638
(1R)
[+497/+1653(15)1
Scheme 5. Benzoannelated derivatives of 8, 14 and 18
The conversion of the ketones 5, 11 and 17 into the single, double, and triple a-diketones, respectively, presented
difficulties. The a-diketones, finally set free by ozonolysis
from the respective a-methylene derivatives, proved to be
increasingly unstable in the order single > double > triple,
but nevertheless could be trapped with o-phenylenediamine, e.g. the hexaketone 29 as triquinoxaline 30, albeit in
drastically decreasing yield (95%, 56%, 9%) (Table 1).
a0
L
0
00
20
Scheme 4. lsomerization of 14 and 18 over Pd/C.
29
The preparatively important, in its details still unclear
tendency of the [2.2.2]-triblattane skeleton to undergo
(acid-catalyzed) i~ornerization~~~
manifests itself in the perepoxidation of ruc-18 : even with carbamic peracids, byproducts and secondary products are formed besides the
trioxides ruc-21 and ruc-22 (about 60% as a ca. 1 : 10 mixture, Table 1).["]
18
21
Angew. Chem. Int. Ed. Engl. 27 (1988) No. 8
22
Received: March 28, 1988 [Z 2682 IE]
German version: Angew. Chem. 100 (1988) 1140
[I] W.-D. Fesser, H. Prinzbach, Tetrahedron 42 (1986) (on page 1800, the
absolute configurations of (-)-6c and ( + ) - 1 must be interchanged (cf.
experimental part)). In the meantime the yield of the subsequent trio1
oxidation has been improved from ca. 50% to 70% (J.-P. Melder, Diplomarbeit, Universitat Freiburg 1986). In a later work on the synthesis of
rac-1 (A. P. Marchand, G. V. M. Sharma, G. S . Annapurna, P. R. Pednekar, J. Org. Chem. 52 (1987) 4784) the "art of citing references" is remarkable.
[2] These triscations will be reported on in collaboration with G. Olah et
al.
[3] M. Nakazaki, Top. Stereochem. 15 (1984) 199, and references cited therein; K. Naemura, Y. Hokura, M. Nakazaki, Tetrahedron 42 (1986) 1763.
[4] K. P. Meurer, F. Vogtle, Top. Curr. Chem. 127 (1985) 1.
0 VCH Verlagsgesellschaft mbH, 0-6940 Weinheim, 1988
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1105
[ 5 ] H.-D. Martin, B. Mayer, Angew. Chem. 95 (1983)281; Angew. Chem Int.
Ed. Engl. 22 (1983)283.
161 In collaboration with G. Snofzke, R. Gleiter, H . Irngartinger.
171 The value of other derivatives of the type I (R = C02H, OH, NH2;
X = 0, NR) derived from (-)-I (( +)-1) as chiral reagents is beiflg investigated.
R
[I I] All the new compounds are characterized by elemental analyses and
spectra (’H, ”C-NMR, IR, MS). See Table 1.
[12] M. Fetizon, M. Jurion, N. T. Anh, J . Chem. Sor. Chem. Commun. 1969.
112.
[I31 W. Perkow, Chem. Ber. 8 7 (1954) 755; E. M.Gaydou, J.-P. Bianchini,
Can. J. Chem. 54 (1976)3626.
[I41 P. E. Eaton, B. Leipzig, J. Org. Chem. 43 (19’78)2483.
1151 E. C. Smith, J. C. Barborak, J. Org. Chem. 41 (1976) 1433.
[16] A. T. Balaban, C. Deleanu, Rev. Rourn. Chim. 32 (1987) 271; cf. J.-P.
Melder, F. Wahl, H. Fritz, H. Prinzbach, Chimiu 41 (1987) 426.
[I?] H.-D. Martin, P. Pfohler, Angew. Chem. 90 (1978)901; Angew. Chem.
Int. Ed. Engl. 17 (1978)847.
[18]The C,-symmetrical 3,8,~4,18-tetraoxaoctacyclo[8.7.1.02~1.05~16.0b~12.07~9o i I . 1 7 .0’”’5]octadecane I1 (C,4H1404),formed on cleavage of one of the
three bisallylic C-C single bonds, has been identified.
[S] Y. E. Eaton, R. A. Hudson, C. Giordano, J. Chem. SOC.Chem. Commun.
1974, 978.
191 U. Schollkopf, 8. Banhidai, H. Fresnelli, R. Mayer, H. Beckhaus, Justus
Liebigs Ann. Chem. 1974, 176’7.
[lo] D. A. Evans, G. L. Caroll, L. K. Truesdale, J. Org. Chem. 39 (1974)914:
W. E. Parham, C. S. Roosevelt, Tetrahedron Left. 1971. 923.
BOOK R E V I E W S
Organic Chemistry-in Color, and Good
Organic Chemistry. By K . P. C. VoNhardt. W. H. Freeman,
Oxford 1987. xxii, 1275pp. + index, paperback,
L 18.95/bound, L 49.95.- ISBN 0-7 167-1915-O/O-71671786-1
This textbook by a competent author is evidence of the
enormous advantage inherent in a first edition, where, in
contrast to revisions of already established textbooks, one
is not encumbered with outdated ideas in previous editions
which are now getting on in years. Thus, modern organic
chemistry terminology and methods (e.g. stereoselective
synthesis and retrosynthesis) and instrumental analysis (’H
and I3C NMR) are given adequate coverage rather than
being squeezed into whatever space is available. Furthermore, the choice of content is, as a matter of course, u p to
date, as it is not necessary to clear out unwanted material.
The organization chosen here, based on functional groups
and their reactions, has been proved by experience to be
especially useful, and is a welcome feature. Each chapter
deals first with the nomenclature of the relevant class of
compounds, followed by structure and physical properties ;
their reactions and mechanisms are then discussed alongside each other. Each chapter contains a summary of the
most important experimental findings. The exercises included are u p to the most modem standard as regards selection and type of examples.
The elaborate four color printing, which the author refers to with some pride as having great didactic value
(“learning simplified by the use of color”), does in fact
seem to be justified. For example, nucleophiles are represented in red and electrophiles in blue, while radicals and
leaving groups are shown in green, thus enabling one to
see at a glance where the individual fragments of a newly
[*I Editor’s comment: But not in ANGEWANDTE CHEMIE, where electron lone pairs are represented by a pair of dots so as to avoid confusion
with negative charges-a point which time and again gives cause for discussion.
1106
formed molecule have come from. In stereochemistry colors are used to denote the sequence of substitutions according to the Cahn-Ingold-Prelog rules, and in spectroscopy the assignment of individual signals to the corresponding molecular fragments is clearly indicated by using
the same color for both. In this consistent use of color it
has not always been possible to avoid the risk of gaudiness
(e.g. on pages 272 and 1041), but one has to accept this in
view of the undeniable advantages of the technique. The
typeface is clear and the structural formulas are spaciously
set out, and this too is a commendable feature from a
learning standpoint. The careful (possibly computeraided?) processing of the text makes it difficult to detect
printing errors, and in any case it would be petty to list
them in a work of this quality.
The treatment of spectroscopy is outstandingly good, including both the introduction to the physical fundamentals
and the applications to organic chemistry, generously illustrated by reproducing spectra of excellent quality. However, the contribution brought to the understanding of the
subject by a photograph of a commercial (NMR) spectrometer, which after all appears as nothing more than a
“black box”-decorated, of course, by the inclusion of a
pretty female assistant-must remain the author’s own secret.
Some examples of the small number of inaccuracies are
as follows: the chlorophyll formula (p. 1040) is incorrect
(as, incidentally, it also is in Streitwieser and Heathcock’s
“Organic Chemistry”); enantiomerically pure amino acids
are obtainable not only by cleavage of racemates and by
enzymic synthesis (pp. 1240f.), but also of course by enantioselective synthesis; in connection with the 95% photochemical conversion of norbornadiene (p. 594), it should
have been mentioned that a sensitizer was needed; in describing the elegant photoreaction using the matrix isolation technique (p. 1164), it would have been better to formulate a starting material that does not release any cyclobutadiene-complexing CO, when irradiated. Or are these
points merely splitting hairs? The author’s concern with
completeness sometimes results in including equations of
complex reactions with scarcely any explanation, e.g. in
Angew. Chem. Int. Ed. Engl. 27 (1988) No. 8
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