organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

2,8-Di­bromo-4,10-di­chloro-6H,12H-5,11-methano­dibenzo[b,f][1,5]diazo­cine

aDepartment of Chemistry and Biomolecular Sciences, Building F7B, Macquarie University, Sydney, NSW 2109, Australia, and bSchool of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
*Correspondence e-mail: andrew.try@mq.edu.au

(Received 31 July 2008; accepted 14 August 2008; online 20 August 2008)

The title compound, C15H10Br2Cl2N2, a 2,8-dibromo-4,10-dichloro Tröger's base analogue derived from 4-bromo-2-chloro­aniline, has a dihedral angle of 110.9 (10)° between the two aryl rings, the largest yet measured for a simple dibenzo analogue.

Related literature

For related literature on the synthesis and crystal structures of dihalogenated Tröger's base analogues, see: Jensen & Wärnmark (2001[Jensen, J. & Wärnmark, K. (2001). Synthesis, pp. 1873-1877.]); Faroughi et al. (2006a[Faroughi, M., Try, A. C. & Turner, P. (2006a). Acta Cryst. E62, o3674-o3675.], 2007a[Faroughi, M., Try, A. C., Klepetko, J. & Turner, P. (2007a). Tetrahedron Lett. 48, 6548-6551.],b[Faroughi, M., Try, A. C. & Turner, P. (2007b). Acta Cryst. E63, o2695.]). For Tröger's base analogues substituted with multiple electron-withdrawing groups, see: Faroughi et al. (2006b[Faroughi, M., Try, A. C. & Turner, P. (2006b). Acta Cryst. E62, o3893-o3894.]); Bhuiyan et al. (2006[Bhuiyan, M. D. H., Try, A. C., Klepetko, J. & Turner, P. (2006). Acta Cryst. E62, o4887-o4888.], 2007[Bhuiyan, M. D. H., Jensen, P. & Try, A. C. (2007). Acta Cryst. E63, o4393.]); Vande Velde et al. (2008[Vande Velde, C. M. L., Didier, D., Blockhuys, F. & Sergeyev, S. (2008). Acta Cryst. E64, o538.]). For reactions of halogenated Tröger's base analogues, see: Jensen et al. (2002[Jensen, J., Strozyk, M. & Wärnmark, K. (2002). Synthesis, pp. 2761-2765.]); Hof et al. (2005[Hof, F., Schar, M., Scofield, D. M., Fischer, F., Diederich, F. & Sergeyev, S. (2005). Helv. Chim. Acta, 88, 2333-2344.]). For literature on racemization of Tröger's base analogues and the effect of substituents ortho to the diazo­cine N atoms, see: Lenev et al. (2006[Lenev, D. A., Lyssenko, K. A., Golovanov, D. G., Buss, V. & Kostyanovsky, R. G. (2006). Chem. Eur. J. 12, 6412-6418.]).

[Scheme 1]

Experimental

Crystal data
  • C15H10Br2Cl2N2

  • Mr = 449.0

  • Orthorhombic, P c a 21

  • a = 7.910 (2) Å

  • b = 12.601 (3) Å

  • c = 15.230 (4) Å

  • V = 1518.0 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 5.64 mm−1

  • T = 294 K

  • 0.30 × 0.12 × 0.07 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: analytical (de Meulenaer & Tompa, 1965[ Meulenaer, J. de & Tompa, H. (1965). Acta Cryst. 19, 1014-1018.]) Tmin = 0.52, Tmax = 0.69

  • 1394 measured reflections

  • 1394 independent reflections

  • 1028 reflections with I > 2σ(I)

  • 1 standard reflection frequency: 30 min intensity decay: none

Refinement
  • R[F2 > 2σ(F2)] = 0.056

  • wR(F2) = 0.061

  • S = 1.61

  • 1394 reflections

  • 189 parameters

  • H-atom parameters constrained

  • Δρmax = 0.98 e Å−3

  • Δρmin = −1.02 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.])

  • Flack parameter: 0.09 (2)

Data collection: CAD-4 (Schagen et al., 1989[Schagen, J. D., Straver, L., van Meurs, F. & Williams, G. (1989). CAD-4 Manual. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4; data reduction: local program; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); program(s) used to refine structure: RAELS (Rae, 1996[Rae, A. D. (1996). RAELS. University of New South Wales, Australia.]); molecular graphics: ORTEPII (Johnson, 1976[Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.]); software used to prepare material for publication: local programs.

Supporting information


Comment top

Tröger's base analogues bearing electron-withdrawing groups were long thought to be difficult, if not impossible, to prepare. However, the synthesis of dihalogenated (Jensen & Wärnmark, 2001), octafluoro (Vande Velde et al., 2008) and tetranitro (Bhuiyan et al., 2007) Tröger's base analogues highlight the possiblities that now exist in terms of incorporating electron-withdrawing groups on the starting anilines. The synthetic utility of halogen-substituted Tröger's base analogue has been demonstrated with their conversion to alkyne- (Jensen & Wärnmark, 2001; Jensen et al., 2002) and functionalized phenyl- (Hof et al., 2005) substituted analogues, among others. It is noteworthy that crystal structures of several other 2,4,8,10-tetrasubstituted Tröger's base analogues exhibit large dihedral angles that are close to that in (I). Tröger's base analogues are known to undergo racemization in acidic solution, however the presence of a substituent at the ortho-position, relative to the bridge nitrogen atoms, has been shown to increase the racemization barrier (Lenev et al., 2006).

The molecular structure of (I) is shown in Fig. 1 and it was prepared as outlined in Fig. 2.

Related literature top

For related literature on the synthesis and crystal structures of dihalogenated Tröger's base analogues, see: Jensen & Wärnmark (2001); Faroughi et al. (2006a, 2007a,b). For Tröger's base analogues substituted with multiple electron-withdrawing groups, see: Faroughi et al. (2006b); Bhuiyan et al. (2006, 2007); Vande Velde et al. (2008). For reactions of halogenated Tröger's base analogues, see: Jensen et al. (2002); Hof et al. (2005). For literature on racemization of Tröger's base analogues and the effect of substituents ortho to the diazocine N atoms, see: Lenev et al. (2006).

Experimental top

4-Bromo-2-chloroaniline (1 g, 4.84 mmol) and paraformaldehyde (232 mg, 7.74 mmol) were added to an ice-cold solution of trifluoroacetic acid (10 ml). The reaction mixture was then stirred in dark at room temperature for 7 days under an atmosphere of argon. The ice-cold reaction mixture was basified by the dropwise addition of a mixture of ammonia (28%, 20 ml) and water (40 ml), followed by the additon of a saturated sodium hydrogen carbonate solution (20 ml). The resultant mixture was then extracted with dichloromethane (3 x 20 ml) and the combined organic layers were washed with brine (40 ml), dried over anhydrous sodium sulfate, filtered and evaporated to dryness. The crude product was chromatographed (silica gel, dichloromethane:hexane 8:2) to afford 2,8-dibromo-4,10-dichloro-6H,12H-5,11-methanodibenzo [b,f][1,5]diazocine (I) (613 mg, 56%) as a white solid and as a racemic mixture: m.p. 471–472 K; 1H NMR (400 MHz, CDCl3) δ 4.21–4.33 (4H, m), 4.55 (2H, d, J 17.3 Hz), 7.04 (2H, d, J 2.1 Hz), 7.41 (2H, d, J 2.1 Hz); 13C NMR (100 MHz, CDCl3) δ 54.37, 67.32, 117.15, 128.49, 130.17, 131.02, 131.71, 142.33. Analysis found: C 40.46; H 2.22; N 6.46; C15H10Br2Cl2N2 requires C 40.13; H 2.25; N 6.24. Single crystals were obtained from slow evaporation from dichloromethane solution of (I).

Refinement top

Hydrogen atoms were included in positions calculated each cycle (C—H = 1.0 Å), and were assigned thermal parameters equal to their bonded atom. The maximum and minimum electron density peaks were located 0.73 and 1.20Å from the Cl2 and Br1 atoms, respectively.

Computing details top

Data collection: CAD-4 (Schagen et al., 1989); cell refinement: CAD-4 (Schagen et al., 1989); data reduction: local program; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: RAELS (Rae, 1996); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: local programs.

Figures top
[Figure 1] Fig. 1. ORTEPII (Johnson, 1976) plot of (I), with ellipsoids at the 10% probability level. H atoms are drawn as spheres of arbitrary radius.
[Figure 2] Fig. 2. Synthetic scheme for the synthesis of (I) showing the numbering system used in naming the compound.
2,8-Dibromo-4,10-dichloro-6H,12H-5,11- methanodibenzo[b,f][1,5]diazocine top
Crystal data top
C15H10Br2Cl2N2Dx = 1.96 Mg m3
Mr = 449.0Melting point: 471 K
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2acCell parameters from 11 reflections
a = 7.910 (2) Åθ = 10–11°
b = 12.601 (3) ŵ = 5.64 mm1
c = 15.230 (4) ÅT = 294 K
V = 1518.0 (7) Å3Prism, colourless
Z = 40.30 × 0.12 × 0.07 mm
F(000) = 872.0
Data collection top
Enraf–Nonius CAD-4
diffractometer
θmax = 25°
ω–2θ scansh = 09
Absorption correction: analytical
de Meulenaer & Tompa (1965)
k = 014
Tmin = 0.52, Tmax = 0.69l = 180
1394 measured reflections1 standard reflections every 30 min
1394 independent reflections intensity decay: none
1028 reflections with I > 2σ(I)
Refinement top
Refinement on F w = 1/[σ2(F) + 0.0004F2]
R[F2 > 2σ(F2)] = 0.056(Δ/σ)max = 0.002
wR(F2) = 0.061Δρmax = 0.98 e Å3
S = 1.61Δρmin = 1.02 e Å3
1394 reflectionsAbsolute structure: Flack (1983), 0 Friedel pairs
189 parametersAbsolute structure parameter: 0.09 (2)
H-atom parameters constrained
Crystal data top
C15H10Br2Cl2N2V = 1518.0 (7) Å3
Mr = 449.0Z = 4
Orthorhombic, Pca21Mo Kα radiation
a = 7.910 (2) ŵ = 5.64 mm1
b = 12.601 (3) ÅT = 294 K
c = 15.230 (4) Å0.30 × 0.12 × 0.07 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer
1394 independent reflections
Absorption correction: analytical
de Meulenaer & Tompa (1965)
1028 reflections with I > 2σ(I)
Tmin = 0.52, Tmax = 0.691 standard reflections every 30 min
1394 measured reflections intensity decay: none
Refinement top
R[F2 > 2σ(F2)] = 0.056H-atom parameters constrained
wR(F2) = 0.061Δρmax = 0.98 e Å3
S = 1.61Δρmin = 1.02 e Å3
1394 reflectionsAbsolute structure: Flack (1983), 0 Friedel pairs
189 parametersAbsolute structure parameter: 0.09 (2)
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br10.8061 (2)0.6867 (1)0.3991 (1)0.0585 (5)
Br20.2324 (2)0.0800 (1)0.0428 (2)0.0527 (5)
Cl10.9770 (5)0.5167 (4)0.0779 (3)0.057 (1)
Cl20.5654 (5)0.0565 (3)0.3603 (3)0.052 (1)
N10.9460 (14)0.3064 (10)0.1658 (8)0.041 (3)
N20.8319 (15)0.1842 (9)0.2739 (8)0.044 (3)
C10.9798 (19)0.2123 (12)0.2198 (10)0.044 (4)
C20.8998 (18)0.3929 (12)0.2193 (10)0.043 (4)
C30.8445 (18)0.3790 (11)0.3054 (8)0.041 (4)
C40.817 (2)0.2693 (12)0.3414 (8)0.049 (4)
C50.6842 (19)0.1696 (11)0.2226 (9)0.039 (4)
C60.6740 (19)0.2086 (11)0.1360 (9)0.036 (4)
C70.8206 (17)0.2753 (12)0.0978 (9)0.040 (4)
C80.9155 (17)0.4984 (13)0.1855 (9)0.043 (4)
C90.8825 (19)0.5861 (12)0.2397 (11)0.048 (4)
C100.839 (2)0.5684 (13)0.3247 (11)0.050 (4)
C110.818 (2)0.4666 (13)0.3570 (10)0.056 (4)
C120.5565 (17)0.1082 (10)0.2538 (8)0.031 (3)
C130.4158 (17)0.0854 (10)0.2036 (8)0.035 (3)
C140.4117 (17)0.1221 (11)0.1168 (9)0.040 (4)
C150.5433 (19)0.1819 (10)0.0853 (9)0.034 (3)
H1C11.07800.22730.25930.044
H2C11.00780.15130.18040.044
H1C40.70080.26600.36740.049
H2C40.90270.25590.38830.049
H1C70.77260.34100.07080.040
H2C70.87940.23260.05170.040
HC90.89060.66000.21620.048
HC110.78250.45670.41950.056
HC130.31940.04380.22860.035
HC150.54110.20610.02280.034
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.060 (1)0.060 (1)0.0549 (9)0.0011 (8)0.001 (1)0.0138 (9)
Br20.0470 (9)0.0650 (9)0.0461 (8)0.0118 (8)0.0026 (9)0.0091 (9)
Cl10.061 (3)0.066 (3)0.044 (2)0.019 (2)0.010 (2)0.000 (2)
Cl20.063 (3)0.056 (2)0.037 (2)0.000 (2)0.006 (2)0.018 (2)
N10.029 (7)0.058 (8)0.037 (7)0.001 (6)0.002 (6)0.003 (6)
N20.046 (7)0.048 (7)0.038 (7)0.004 (6)0.009 (6)0.020 (6)
C10.029 (9)0.067 (9)0.036 (8)0.005 (8)0.016 (7)0.012 (8)
C20.051 (9)0.043 (9)0.034 (8)0.009 (8)0.020 (8)0.006 (7)
C30.045 (9)0.059 (9)0.019 (8)0.012 (8)0.004 (7)0.005 (7)
C40.083 (9)0.053 (8)0.013 (7)0.004 (9)0.006 (7)0.007 (7)
C50.048 (9)0.043 (9)0.026 (7)0.000 (7)0.013 (7)0.007 (7)
C60.039 (8)0.042 (8)0.026 (8)0.010 (8)0.002 (6)0.006 (7)
C70.037 (8)0.052 (9)0.030 (8)0.007 (8)0.007 (7)0.002 (7)
C80.029 (8)0.062 (9)0.039 (9)0.002 (8)0.002 (7)0.004 (9)
C90.047 (9)0.038 (9)0.059 (9)0.010 (8)0.001 (8)0.007 (8)
C100.047 (9)0.057 (9)0.046 (9)0.005 (8)0.017 (8)0.007 (8)
C110.085 (9)0.052 (9)0.029 (8)0.011 (9)0.009 (9)0.007 (8)
C120.037 (8)0.032 (8)0.024 (7)0.009 (7)0.010 (6)0.002 (6)
C130.046 (9)0.043 (9)0.016 (6)0.014 (8)0.001 (6)0.000 (7)
C140.029 (8)0.039 (8)0.052 (9)0.006 (7)0.010 (7)0.015 (8)
C150.034 (8)0.039 (8)0.027 (7)0.004 (7)0.009 (7)0.004 (7)
Geometric parameters (Å, º) top
Br1—C101.890 (15)C4—H2C41.000
Br2—C141.888 (14)C5—C61.410 (18)
Cl1—C81.724 (14)C5—C121.358 (18)
Cl2—C121.750 (13)C6—C71.55 (2)
N1—C11.468 (18)C6—C151.333 (19)
N1—C21.409 (17)C7—H1C71.000
N1—C71.487 (18)C7—H2C71.000
N2—C11.474 (19)C8—C91.40 (2)
N2—C41.491 (18)C9—C101.357 (19)
N2—C51.417 (18)C9—HC91.000
C1—H1C11.000C10—C111.39 (2)
C1—H2C11.000C11—HC111.000
C2—C31.394 (18)C12—C131.381 (17)
C2—C81.43 (2)C13—C141.402 (18)
C3—C41.50 (2)C13—HC131.000
C3—C111.37 (2)C14—C151.371 (19)
C4—H1C41.000C15—HC151.000
C1—N1—C2110.4 (12)N1—C7—C6112.5 (11)
C1—N1—C7107.4 (11)N1—C7—H1C7108.7
C2—N1—C7115.7 (11)N1—C7—H2C7108.7
C1—N2—C4106.0 (11)C6—C7—H1C7108.7
C1—N2—C5112.2 (11)C6—C7—H2C7108.7
C4—N2—C5114.1 (12)H1C7—C7—H2C7109.5
N1—C1—N2111.3 (11)Cl1—C8—C2119.3 (11)
N1—C1—H1C1109.0Cl1—C8—C9120.4 (12)
N1—C1—H2C1109.0C2—C8—C9120.2 (12)
N2—C1—H1C1109.0C8—C9—C10118.6 (15)
N2—C1—H2C1109.0C8—C9—HC9120.7
H1C1—C1—H2C1109.5C10—C9—HC9120.7
N1—C2—C3121.9 (14)Br1—C10—C9118.5 (13)
N1—C2—C8119.2 (12)Br1—C10—C11120.0 (11)
C3—C2—C8118.8 (13)C9—C10—C11121.4 (15)
C2—C3—C4120.3 (13)C3—C11—C10121.6 (14)
C2—C3—C11119.1 (14)C3—C11—HC11119.2
C4—C3—C11120.6 (12)C10—C11—HC11119.2
N2—C4—C3113.5 (10)Cl2—C12—C5120.5 (12)
N2—C4—H1C4108.4Cl2—C12—C13117.9 (10)
N2—C4—H2C4108.4C5—C12—C13121.6 (13)
C3—C4—H1C4108.4C12—C13—C14118.2 (13)
C3—C4—H2C4108.4C12—C13—HC13120.9
H1C4—C4—H2C4109.5C14—C13—HC13120.9
N2—C5—C6121.2 (13)Br2—C14—C13119.2 (11)
N2—C5—C12119.6 (13)Br2—C14—C15121.0 (11)
C6—C5—C12118.9 (15)C13—C14—C15119.6 (13)
C5—C6—C7119.8 (13)C6—C15—C14121.6 (13)
C5—C6—C15119.9 (14)C6—C15—HC15119.2
C7—C6—C15120.1 (12)C14—C15—HC15119.2
C2—N1—C1—N257.5 (15)C2—C3—C11—C102 (2)
C2—N1—C1—H1C162.8C2—C3—C11—HC11177.7
C2—N1—C1—H2C1177.8C4—C3—C11—C10178.6 (16)
C7—N1—C1—N269.4 (15)C4—C3—C11—HC111.4
C7—N1—C1—H1C1170.3N2—C5—C6—C74 (2)
C7—N1—C1—H2C150.8N2—C5—C6—C15171.2 (13)
C1—N1—C2—C318.2 (18)C12—C5—C6—C7177.9 (12)
C1—N1—C2—C8159.5 (13)C12—C5—C6—C152 (2)
C7—N1—C2—C3103.9 (16)N2—C5—C12—Cl25.4 (18)
C7—N1—C2—C878.3 (17)N2—C5—C12—C13175.2 (12)
C1—N1—C7—C644.6 (15)C6—C5—C12—Cl2179.1 (10)
C1—N1—C7—H1C7165.1C6—C5—C12—C132 (2)
C1—N1—C7—H2C775.8C5—C6—C7—N110.2 (17)
C2—N1—C7—C679.1 (15)C5—C6—C7—H1C7130.7
C2—N1—C7—H1C741.3C5—C6—C7—H2C7110.2
C2—N1—C7—H2C7160.4C15—C6—C7—N1174.2 (13)
C4—N2—C1—N169.8 (13)C15—C6—C7—H1C753.8
C4—N2—C1—H1C150.5C15—C6—C7—H2C765.3
C4—N2—C1—H2C1169.9C5—C6—C15—C144 (2)
C5—N2—C1—N155.3 (16)C5—C6—C15—HC15176.1
C5—N2—C1—H1C1175.6C7—C6—C15—C14179.5 (12)
C5—N2—C1—H2C165.0C7—C6—C15—HC150.5
C1—N2—C4—C342.4 (15)Cl1—C8—C9—C10178.1 (12)
C1—N2—C4—H1C4163.0Cl1—C8—C9—HC91.9
C1—N2—C4—H2C478.2C2—C8—C9—C101 (2)
C5—N2—C4—C381.5 (16)C2—C8—C9—HC9178.6
C5—N2—C4—H1C439.1C8—C9—C10—Br1176.8 (11)
C5—N2—C4—H2C4157.9C8—C9—C10—C114 (3)
C1—N2—C5—C617.3 (19)HC9—C9—C10—Br13.2
C1—N2—C5—C12156.2 (13)HC9—C9—C10—C11176.3
C4—N2—C5—C6103.2 (14)Br1—C10—C11—C3178.6 (12)
C4—N2—C5—C1283.3 (16)Br1—C10—C11—HC111.4
N1—C2—C3—C46 (2)C9—C10—C11—C32 (3)
N1—C2—C3—C11173.3 (14)C9—C10—C11—HC11178.1
C8—C2—C3—C4176.4 (14)Cl2—C12—C13—C14176.9 (10)
C8—C2—C3—C114 (2)Cl2—C12—C13—HC133.1
N1—C2—C8—Cl14.3 (19)C5—C12—C13—C143.7 (19)
N1—C2—C8—C9175.2 (13)C5—C12—C13—HC13176.3
C3—C2—C8—Cl1177.9 (11)C12—C13—C14—Br2173.5 (9)
C3—C2—C8—C93 (2)C12—C13—C14—C152.1 (18)
C2—C3—C4—N28 (2)HC13—C13—C14—Br26.5
C2—C3—C4—H1C4128.1HC13—C13—C14—C15177.9
C2—C3—C4—H2C4113.1Br2—C14—C15—C6177.3 (11)
C11—C3—C4—N2173.3 (14)Br2—C14—C15—HC152.7
C11—C3—C4—H1C452.7C13—C14—C15—C62 (2)
C11—C3—C4—H2C466.1C13—C14—C15—HC15178.3

Experimental details

Crystal data
Chemical formulaC15H10Br2Cl2N2
Mr449.0
Crystal system, space groupOrthorhombic, Pca21
Temperature (K)294
a, b, c (Å)7.910 (2), 12.601 (3), 15.230 (4)
V3)1518.0 (7)
Z4
Radiation typeMo Kα
µ (mm1)5.64
Crystal size (mm)0.30 × 0.12 × 0.07
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionAnalytical
de Meulenaer & Tompa (1965)
Tmin, Tmax0.52, 0.69
No. of measured, independent and
observed [I > 2σ(I)] reflections
1394, 1394, 1028
Rint?
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.056, 0.061, 1.61
No. of reflections1394
No. of parameters189
No. of restraints?
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.98, 1.02
Absolute structureFlack (1983), 0 Friedel pairs
Absolute structure parameter0.09 (2)

Computer programs: CAD-4 (Schagen et al., 1989), SIR92 (Altomare et al., 1994), RAELS (Rae, 1996), ORTEPII (Johnson, 1976), local programs.

 

Acknowledgements

The authors thank Macquarie University for the award of a Macquarie University Research Development Grant to ACT.

References

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