close

Вход

Забыли?

вход по аккаунту

?

Boroboration of CO with Tri-tert-butylazadiboriridine.

код для вставкиСкачать
3.2 (2q; SiMe). IR (CCI,): V
=
1600cm" (BH,B). MS(70eV): mjz 484
(Me,22%),469(Me-CH,,66),411(Me-SiMe,. 58), 242(1/2Me, 57),
Fig. I. Centrosymmetric molecular structure of 3. Selected distances, angles,
and torsion angles ([A] and ["I. standard deviations in parentheses): B...B
1.856(3), B-HI 1.266(15),B-HI 1.280(14),B-C 1.605(2),C-Sil 1.918(2),Sil-C2
1.896(2),C2-B 1.586(3); B-HI-B 93.6(9), Hl-B-H1'86.4(9), C-B...B 112.7(2),
C-B-C2 137.5(1), B-C-Sil lOl.o(l). C-Sil-C2 104.3(1), Sil-C2-B 103.9(1), SilC-Si2 110.6(1), Sil-C-Si3 113.9(1), Si2-C-Si3 112.7(1), Cl-Sil-C3 106.7(1); BC-Sil-C2 27.0, C-Sil-C2-B - 27.6, Sil-C2-B-..B 17.5, Sil-C-B--.B- 17.7,
C2-B-..B-C 0.4.
Compound 3 has Ci symmetry. The atoms B, B , C, C', C2,
and C2' are arranged in a nearly coplanar fashion in two
nonplanar five-membered rings sharing a common B-B
edge. The parallelogram B-HI -B'-HI ' lies nearly perpendicular to the planes of those atoms. The distance B . . . B
(1.856 A) is comparable to the B...B distance in truns-1,2bis(trisyl)diborane(6), [(Me3Si)3C],B,H,151 (1 239 A), and
markedly longer than the B.. . B distance in B,H, (1.76 A).[61
The 1,5-disila-3,7-diboracyclooctanestructure of 3, with a
double 3,7-transannular H bridge, resembles the established
structure of a likewise transannularly bridged 1,6-diboracy~lodecane.['~
Obviously, intermediates in the reaction of 1 with Na/K
might be either trisylboranediyl, (Me,Si),CB:, or dichlorobis(trisyl)diborane(4), (Me,Si)3C(C1)B-B(C1)C(SiMe3)3,
which could undergo dimerization or a second dechlorination step, respectively, to give 2. Intramolecular additions
of C-H bonds to unsaturated systems, as presumed to occur
in the stabilization of 2 to give the isolated product 3,
are well known. Examples in boron chemistry include the
stabilization of RB G 0 (R = 2,4,6-tri-tert-butylphenyl),
C6F,B = NR (R = mesityl), and R,NB = NNR, (NR, = 2,6dimethylpiperidino).181
Experimental Procedure
1.2: 2,l- Bis[2,2-dimethyl- 1,l- bis(trimethylsilyl)-2-silapropdne- 1,3,diyl]diborane(6). 3: A solution of 1 (3.0 g) in 25 mL of hexane was treated at room
temperature with 0.90 g of NajK alloy (1 : 3 ) .The reaction mixture was refluxed
for 4 d and then filtered. The filtrate was concentrated until the crude product
started to crystallize. Recrystallization once from hexane and twice from diethyl
ether afforded 0.36 g of colorless 3 (15%; m p. 250°C) The product can be
handled under air without decomposition.
Received: April 2, 1990 [Z 3891 IE]
German version: Angew. Chem. 102 (1990) 909
CAS Registry numbers: 1, 124408-70-4;3, 128054-44-4
[ l ] P. Paetzold, Adv. Inorg. Chem. 31 (1987) 123; R. Boese, P. Paetzold, A.
Tapper, R. Ziembinski, Chem. Ber. 122 (1989) 1057; H. Bock, L. S. Ceder-
baum. W. von Niessen, P. Paetzold, P. Rosmus, B. Sofouki, Angew. Chem.
101 (1989) 77; Angew. Chem. Inr. Ed. EngL 28 (1989) 88.
[2] S. S . Al-Juaid, C. Eaborn, J. Chem. Soc. Dalton Trans. 1989, 447.
131 3: NMR [CDCI,, 25 "C. 80 MHzjTMS ('H), 32.08 MHz/Et,O. BF, ("B),
67.88 MHz/TMS ('3C)]: d('H) = - 0.12-0.07 (4H, CH,), 0.11 (s, 36H,
SiMe,), 0.23 ( s , 12H; SiMe,); 6("B) = 33.2; 6(I3C) = 0.1-6.5 (BC), 2.2,
900
(0 VCH
Veriagsgesehschaft mbH. 0-6940 Wemhejm, 1990
100).
73
141 Single crystals of 3 were obtained from diethyl ether: a = 15.950(1),
b = 8.938(1), c = 21.417(2) A, p = 99.63". V = 3010.213) A,, Z = 4,
= 1.070 g ~ m - C2/c
~ , (No. 15); crystal dimensions 0.50 x 0.39 x 0.21 mm3,
T = 125 K, measuring range 3 I 2 B 545"; 1981 unique reflections, 1891
observed with Fo 2 4u(F); anisotropic temperature factors for the non-hydrogen atoms; 148 refined parameters; R = 0.029, R, = 0.036. Further details of the crystal structure investigation may be obtained from the Fachinformationszentrum Karlsruhe, Gesellschaft fur wissenschaftlich-technische
Information mbH, D-7514 Eggensteln-Leopoldshafen 1 (FRG), on quoting
the depository number CSD-320101, the names of the authors, and the
journal citation.
[5] S . S . Al-Judid, C. Eaborn, P. B. Hitchcock. J. D. Smith, .
I
Organomer.
Chem. 385 (1990) 13; P. Paetzold, L. Geret, R. Boese, ibrd. 385 (1990) 1.
[6] D. S . Jones, W. N. Lipscomb, J. Chem. Phys. 51 (1969) 3133.
[7] M. Yalpani, R. Boese, R. Koster, Chem. Ber. 120 (1987) 1843. Cf. also R.
Koster in: Houhen- Weyl-Meihoden der Organrschen Chemie, Band XllIj3a,
Thieme, Stuttgart 1982, p. 328ff.
[8] M. Groteklaes, P. Paetzold, Chem. Ber. 121 (1988) 809; P. Paetzold, A.
Richter, T. Thijssen. S . Wurtenberg, ihid. 112 (1979) 3811; W. Pieper, D.
Schmitz, P. Paetzold, ibid. 114 (1981) 3801.
Boroboration of CO with
Tri-tert-butylazadiboriridine
By Peter Paetzold,* Burkhurd Redenz-Stormanns
and Rolund Boese *
Tri-tert-butylazadiborindine(l)[']reacts at - 78 "C with
CO according to Equation (1) to form the tricyclic product
2; NMR monitoring of the reaction indicates that it is complete. We have isolated colorless, crystalline 2 in 71 % yield.
The constitution of 2 was established from the NMR and
mass spectra,['] and the unexpected structure was confirmed
by X-ray structure analysis (Fig.
In the centrosymmetric molecule 2, two CBN three-membered rings are joined in
a spirocyclic fashion to the central, planar six-membered
ring, and the planes of neighboring rings are nearly perpendicular to each other. The tBu groups at B3 and B3' are
displaced toward the ring 0 atoms by the neighboring threemembered rings, as shown by the angles CI'-B3-C30 and
0-B3-C30 (128 and 113", respectively). The B-0 distance of
1.36 8, supports the assumption of appreciable 7c contributions to the B-0 bonding. Especially striking is the B-N
distance of 1.33A, the shortest B-N double bond so far
The surprising formation of 2 according to Equation (1)
may be explained as follows: First, the carbene-like C atom
of CO inserts into the B-B bond of 1 with formation of a
four-membered ring; that is, the C atom is "boroborated".
The four-membered ring then undergoes cyclodimerization
['I
Prof. Dr. P. Paetzold, B. Redenz-Stormanns
Institut fur Anorganische Chemie der Technischen Hochschule
Templergraben 55, D-5100 Aachen (FRG)
Dr. R. Boese
Institut fur Anorganische Chemie der Unwersitat-Gesamthochschule
Universitdtsstrdsse 5 -7, D-4300 Essen (FRG)
0570-0833~90/0808-0900$ 3 SO+ .25/0
Angew. Chem. 1nr. Ed Engl 29 (1990) N o 8
Flg. 1. Molecular structure of 2 (hydrogen atoms omitted). Selected distances
and angles ([A] and [“I, standard deviations in parentheses): B3-0 1.360(5),
0-C1 1.453(5), Cl-B3’ 1.558(6), B3-C30 1.600(6), C1-B2 1.551(6), Cl-N1
1.459(5). B2-Nl 1.329(9), B2-C20 1.529(9), N1-ClO 1.492(8); Cl‘-B3-0
118.8(4). B3-0-C1 124.6(3), O-CI-BY 116.5(3), B2-Ct-Nl 52.3(3), C1-B2-Nl
60.3(3), Cl-Nl-B2 67.4(3), Cl’-B3-C30 128.0(3), 0-B3-C30 113.1(3).
along a BCO unit to form the corresponding six-membered
ring. Finally, sigmatropic migration of the amino groups
from the B atoms to the C atoms results in rearrangement to
2 [Eq. (211. This proposal is supported by the “alkyloboration” of CO with BR;, which occurs according to Equation
(3) in a fully analogous fashion.‘’]
R’
Fig. 2. Molecular structure of 3. Selected distances, angles, and torsion angles
standard deviations in parentheses): Cl-N 1.429(4),N-B2 1.449(5),
8 2 - 0 1.399(4), 0-B1 1.379(4), B1-Cl’ 1.557(5), Cl-Cl’ 1.390(6), B1-C2
1.581(4), B2-C6 1.594(5), N-C10 1.52015); C1’-C1-N 120.5(3), Cl-N-B2
115.3(3), N-B2-0 11533). B2-0-B1 121.9(3), 0-Bl-Cl‘ 112.0(2), C1’-BGC2
130.2(3), O-Bl-C2 116.743); C1’-Cl-N-B2 30.6, Cl-N-B2-0 35.1, N-B2-0-B1
0.2, B2-0-Bl-C1‘36.6, Bl-Cl’-Cl-N -6.7, C1’-Cl-N-ClO - 128.5,Cl-Cl’-BlC2 125.0, Bl-O-B2-C6 173.2, Bl-Cl’-Cl-Bl’ - 180.0.
([A] and I“],
at B’,N project “below” and “above”, respectively, the ring
framework. The pyramidal distortion at these four ring
atoms caused by the nonplanarity of the ring framework is
thereby largely compensated. In the formation of 3, the C-0
triple bond is opened at - 30 “C. Presumably, the Fe atom of
an unknown intermediate is involved catalytically in this
process.
The smooth reaction of the carbene-like molecule CO indicates that nitrenes or their precursors should react similarly. We therefore carried out the reaction of 1 with butyl azide,
which resulted in loss of N, and formation of diazadiboretidine 4 in 65% yield [Eq.-(S)]. The constitution of 4 was
R’
R
(5)
4
Irradiation of Fe(CO), in the presence of 1 at -30°C
results in a product completely different from 2 but also
corresponding to a 1 :1 reaction of 1 and CO. The colorless,
crystalline compound 3 is formed in 34 % yield [Eq. (4)].
R
R
3
NMR and mass spectral6’ are in agreement with structure
3, which was confirmed by an X-ray structure analysis
(Fig. 2).17] In the centrosymmetric molecule 3, which is similar to naphthalene, the central ring atoms C1, Cl’, BI, Bl’,
N, and N are arranged in a planar fashion, but the trapeziform outer parts of the ring, Bl-O-B2-N and Bl’-O-B2‘-N’,
form an angle of 37.4” with the plane defined by the central
ring atoms. The distances between neighboring ring atoms
lie between those of typical single and double bonds involving the respective elements. This indicates a naphthalene-like
cyclic delocalization of the a-electron systems despite the
nonplanarity of the framework. The tBu groups at B1, N and
Angew Chem I n l . Ed Engl. 29 (1990) N o 8
0 VCH
established unambiguously from the NMR and mass spectra.[’] The diazadiboretidines (tBuBNtBu), and (BuBNtBu),
related to 4 have been well investigated stru~turally!~~
In the
formation of 4, the nitrene BUN: formally undergoes boroboration. First, one of the B atoms of 1 must attack the N1
atom of the N, group. The second step could involve either
1,I boroboration or 1,3 boroboration of the N, group to give
a six-membered ring, followed by loss of N,. Product 4 corresponds to the hypothetical intermediate in Equation (2).
CO or BUN, do not react with the open-chain diborane(4)
tBu(Me,N)B-B(NMe,)tBu, which is comparable to 1. The
boroboration tendency of 1 thus depends on its three-membered ring structure.
Experimental Procedure
1.2,5,7,8,10-Hexa-~er~-butyl-4,9-dioxa-l,7-diaza-2,5,8,10-tetraboradispiro[2.2.2.2]decane,2: CO was bubbled through a solution of 1 (0.62 g) in 50 mL of
pentane at - 78 “C for 30 min. Compound 2 (0.50 g, 71 %)crystallized from the
reaction solution
1,3,5,7-tetraboranaphthaI1,3,4,5,7,8-Hexa-zerr-butyl-2,6-dioxa-4,8-diazaene, 3: A solution of 1 (1.04 g) and Fe(CO), (0.98 g) in 60 mL of hexane was
irradiated (254 nm) at -30°C for 24 h. All volatiles were then removed under
vacuum at room temperature. Compound 3 (0.40 g, 34 %) was crystaiiized from
ether.
Verlagsgesellschafl mbH, 0-6940 Wernheim, 1990
0570-0S33~90/0808-0901$3.50+ 2210
901
l-Butyl-2,3,4-tri-terr-butyl-l,3,2,4-diazadiboretidine,4. Compound 1
(0.80 g) and butyl azide (0.39 g) were combined in 10 mL of pentane at 0 "C and
the resulting solution was stirred for 30 min at room temperature. Distillative
workup gave 4 (0.70 g, 65%) as a colorless liquid at 70 'C/O.Ol Torr.
size and shape of cyclophanes and host compounds. Comparison of the angles in adamantane and benzene (Scheme 1)
shows that the bridgehead bonds in 1,3-position, like the
m-phenylene bonds, form an angle of ca. 120".
Received: April 17, 1990 [Z 3912 IE]
German version: Angew. Chem 102 (1990) 910
CAS Registry numbers:
1, 109976-00-3; 2, 128270-57-5; 3, 128270-58-6; 4, 128270-59-7; Fe(CO),.
13463-40.6.
111 R. Boese, B. Krockert, P. Paetzold, Chem. Ber. 120 (1987) 1913.
[2] 2: NMR (CDCI,; 25°C; 60 MHz/TMS ('H), 32.08 MHz/Et,O. BF, ("B),
67.88MHz/TMS (I3C)): 6('H) = 0.72, 1.12, 1.29 (3s. 1 : l : l ; 3tBu);
=)28.7, 28.9, 30.8 (3 q ; Me of 3 tBu),
6("B) = 28.4, 48.1 (2 s, 1 : 1); c ~ ( ' ~ C
53.5 (s; C1 of NrBu); the two expectedly broad BC-' ,C singlets could not be
found. MS (70eV): m / z 470 (Me, 68%), 413 (Me - C,H,, 70), 357
(Me - C,H9 - C,H,, SO), 301 (Ma - CaH9- 2C4H8,100).
[3) Single crystals of 2 were obtained from pentane; a = 9.3161(18),
b = 9.666(2), C = 10.7385(17)A, z = 69.941(14), j3 = 80.517(13), 7 =
62.474(13)", V = 805.5(2) A3, 2 = 1, eCalcd
= 0.969 g cm-,, PI (No. 2);
crystal dimensions 0.12 x 0.25 x 0.13 mm3; T = 155 K; measuring range
3 < 2 8 I 4 5 " ; 2113 unique reflections, 1323 observed with F, 2 4.0 o ( F J ;
anisotropic temperature factors for the non-hydrogen atoms; 181 refined
parameters R = 0.071, R, = 0.070. Further details of the crystal structure
investigation my be obtained from the Fachinformationszentrum Karlsruhe, Gesellschaft fur wissenschaftlich-technische Information mbH.
D-7514 Eggenstein-Leopoldshafen 2 (FRG), on quoting the depository
number CSD-320105, the names of the authors, and the journal citation.
[4] P. Paetzold, Adv. Inorg. Chem. 3 f (1987) 123.
[5] A. Pelter, K. Smith, H. C. Brown: Borane Reagents, Academic Press, London 1988, p. 239.
[6] 3:NMR(cf.[Z]):&('H) =0.99, 1.06, 1.14(3s, 1:1:1;3tBu);d(iiB) =37.0,
46.3 (2 s. 111); 6(',C) = 28.5, 29.0, 32.3 (3 q; Me of 3 rBu), 55.3 (s; CI of
NrBu), 146.5 (s; BCN); further BC-13C singlets were not observed.
MS (70eV): m / z 470 (Ma, 96%). 413 (Ma - C,H,, 70). 357
(Ma - C,H9 - C4H8,50), 301 (Me - C4H9- 2 C,H8, 100).
17) Single crystals of 3 were obtained from pentane; a = 8.164(2),
b = 19.250(5), c = 10.190(5)A, j3 = 109.39(3)", V = 1510.6A3, 2 = 2,
ecllsd= 1.033 g ern-,, P2Jc (No. 14); crystal dimensions 0 . 1 2 ~ 0 . 1 4 ~
0.21 mm3; T = 103 K; measuring range 3 9 2 8 2 44'; 1861 unique reflections, 1348 observed with F, 5 40(F); anisotropic temperature factors for
the non-hydrogen atoms; 190 refined parameters, R = 0.05, R, = 0.063.
For further details, see [3], CSD-320104.
[8] 4: NMR (Cf. [2]): 6(lH) = 0.80 - 1.20 (4H; C-CH,-CH,C of Bu), 0.89 (t,
3H; CH3 of Bu), 1.06 (s, 18H; 2 BrBu), 1.21 (s, 9 H ; NrBu), 2.99 (t. 2 H ;
NCH,);b("B) = 42.7;6(13C) = 14.3(q;C40fBu),20.5(t;C3ofBu),29.4
(4; C2 of BtBu), 34.4 (4; C2 of NtBu), 37.4 (t; C2 of Bu), 42.7 (t; C1 of Bu),
48.8 (s; C1 of NrBu); the BC-"C singlet was not found. MS: m / z 278 (Me,
39%), 263 (Me - CH,, loo), 235 ( M e - C,H,, 71), 221 (Me - C4H9,
36).
[9] P. Paetzold, E. Schroder, G. Schmid, R. Boese, Chem. Ber. 118 (1985) 3205;
P. Paetzold, C. von Plotho, G. Schmid, R. Boese, B. Schrader, D. Bougeard,
U. Pfeiffer, R. Gleiter, W. Schafer, ibid. 117 (1984) 1089.
Scheme 1
The stereochemistry of the new hydrocarbon phane 1,
which we designed with this consideration in mind, was expected to be fundamentally different from that of the known
[2.2]metacyclophane2, since three intraannular Hi hydrogen
atoms project into the interior of the ten-membered ring.
2
1
The synthesis of 1 (m.p. 78-79.5") was accomplished via
the dithia[3.3]cyclophane route, starting from 1,3-bis(mercaptomethy1)benzene and 1,3-bis(bromomethyl)adamantane,"] to give dithia[3.3]phane 3 (40 % yield),''] followed by
sulfone pyrolysis (50 % yield)13' (Scheme 2).
Br
Br
L.4-
1
4
Scheme 2. a) High-dilution technique, 2 equiv. NaOH, EtOH/C6H6(4: l), 78 h
reflux, 12 h room temperature, 40%; b) HOAc, H,O, (30%), 5 h reflux, 65%;
c)
Torr, 550°C. 50%.
The First Clamped and Strongly Deformed
Adamantane **
B y Fritz VogtIe,* Joachim Dohm, and Kari Rissanen
Can benzene rings in strained macrocycles be replaced by
adamantane building blocks? If so, this would offer a general
approach to varying the lipophilicity, ring strain, and cavity
[*I Prof. Dr. F. Vogtle, DiplLChem. J. Dohm
Institut fur Organische Chemie und Biochemie der Universitlt
Gerhard-Domagk-Strasse 1
D-5300 Bonn 1 (FRG)
[**I
902
The "[2.2](1,3)adamantanometacyclophane" lL4I exhibits
an intense molecular peak in the mass spectrum ( m / z 266)
and characteristic 'H and I3C NMR spectra. The signals of
HI and HI' are strongly shifted upfield (6 = - 0.10 and
+ 0.06),r51 whereas Hi of the benzene ring absorbs at
6 =7.75. The signals of dithiaphane 3 and disulfone 4 are
even more strongly shifted upfield (up to 6 = - 2.18; cf.
Table 1).
Dr. Kari Rissanen
Department of Chemistry
University of Jyvaskyla
Kyllikinkatu 1 - 3
SF-40100 Jyvaskyla (Finnland)
This work was supported by the Deutsche Forschungsgemeinschaft (Sonderforschungsbereich 334: Interactions in Molecules), the Fonds der
Chemischen Industrie (doctoral fellowship for .f D.), and Bayer AG,
Leverkusen (donation of adamantane). We thank Dr. G. Eckhardr and C.
Schmidt for the EI mass spectra and NMR spectra, respectively.
0 VCH VerlagsgeselischaJi mbH. 0-6940 Weinheim. 1990
0570-0833/90/0808-0902 S 3.50+.25/0
3
5
Angew. Chem. Int. Ed. Engl. 29 (1990) No. 8
Документ
Категория
Без категории
Просмотров
1
Размер файла
348 Кб
Теги
tri, boroboration, butylazadiboriridine, tert
1/--страниц
Пожаловаться на содержимое документа