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[Fe2(CO)6(/J-SN)]_ (2) which reacts with halides of phosphorus, arsenic, silicon, germanium, tin and boron by formation of ..... Fe2(CO)6[/i-SN-P(NCBu)CH2)->CH'>] (7b) (1 g in C7DS,. -20°C. ..... (C6D6): 6i3C = 20.2 (C(CH3)3), 27.9 (C(CH3)3), 128.1 (o-. Ph), 131.0 .... C2H6, 80), 402 (M+-12CO-OMe2, 15), - IR (cm-1):.
N-Functionalization of the Tetrahedrane Fe2(CO)6(/z-SNH) Max Herberhold*, U w e Bertholdt, Wolfgang M iliu s, Bernd W rackmeyer Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth Dedicated to Prof. Dr. Lothar Beyer on the occasion of his 60th birthday Z. Naturforsch. 51 b, 1283-1289 (1996); received March 27, 1996 Azadiferrathia, Tetrahedrane, Cluster Anion, Element-Nitrogen Bonds, NMR Spectra The azadiferrathia tetrahedrane, Fe 2(CO) 6(£/-SNH) (1), was deprotonated to give the anion [Fe 2(CO) 6(/J-SN)]_ (2) which reacts with halides of phosphorus, arsenic, silicon, germanium, tin and boron by formation of element-nitrosen bonds. The new compounds were characterized by their IR. N M R ('H , mB, i3C, i5N, 29S i,3 P, m S n)and mass spectra. The molecular structure of [Fe2(CO)6(A/-SN-SiMe2CH 2-)]2 (11) was determined by X-ray structure analysis (space group P i; triclinic; a = 799.8(2), b = 958.5(2), c = 1035.7(2) pm, a = 86.30(2)°, (3 = 81.27(2)°, 7 = 69.90(2)°).

Introduction

Results and Discussion

The reaction of carbonyliron complexes with bis(trimethylsilyl)sulfurdiimide, M e3Si(NSN)SiMe3, followed by chromatography on silica, leads to the azadiferrathia tetrahedrane 1 [1]. The corresponding anion 2 is formed by deprotonation using sodium [2], "BuLi in hex­ ane or DBU (l,8-diazabicyclo[5.4.0]undec-7-ene) [3] [eq. (1)]. It was already shown that 2 reacts with Me^'BuSiCl to give the N-silylated complex Fe2(CO)6(//-SN-SiM e2'Bu) [2], and that N-organosubstituted derivatives Fe2(CO)6(/u-SN-R) are ac­ cessible from the reaction of 2 with carbenium or trialkyl oxonium cations [3], These successful trans­ formations of 2 prompted us to start a systematic study of the N-functionalization of 1. Here we de­ scribe the new complexes which contain group 15 (phosphanyl, arsanyl), group 14 (silyl, germyl. stannyl) and group 13 (boryl) substituents at the nitrogen atom.

Syntheses

(i)

/ N ------S

/> < S \

x

-N»7

V

A

-------- 5Ü---------C4H10, -Li

(OC)3Fe —---------Fe(CO )3 \

DBU

f

©

N S

/X \\

(OC^Fe -- ---------Fe(CO>3 2

* Reprint requests to Prof. Dr. M. Herberhold. 0 9 3 9 -5 0 7 5 /9 6 /0 9 0 0 - 1 2 8 3 $ 0 6 .0 0

The reactions of the anion 2 with various element halides are summarized in Scheme 1. Apparently, any triorganosilyl, -germyl or -stannyl chloride can be used to prepare complexes of the type 3 - 5 . The reactions of 2 with bis(chlorosilyl) compounds, as shown in Scheme 2, afford the new compounds 9 - 11, of which 11 was studied by X-ray diffraction (vide infra). It appears that the reaction of 2 with arsenic chlo­ rides is also straightforward, and the products 6a and 6b are isolated in moderate to good yields. In con­ trast, 'BU2PCI does not react with 2. If the reaction of 2 with either 'P nP C l or Cy2PCl is monitored by IR spectroscopy , the presence of the desired prod­ ucts can be observed for about 5 - 1 0 min at -78°C, but thereafter decomposition into unidentified com­ pounds takes place, as is also apparent from the 11P NMR spectra of reaction solutions. However, it turns out that 2 reacts with cyclic diaminophosphorus halides bearing bulky substituents ('Bu groups) at the nitrogen atoms to give reasonably stable prod­ ucts (7a, 7b). Compounds 7c and 7d with the less bulky N 'Pr groups had to be characterized at low temperature. The boron-substituted tetrahedranes 8 can be readily isolated if at least one dialkylamino group is linked to boron. All attempts to obtain dialkylboryl derivatives failed. Although 2 reacts with the 9-BBN derivatives 9-chloro- and 9-methoxyborabicyclo[3.3.1jnonane, it was not possible so

© 1996 Verlag der Z eitschrift für N aturforschung. A ll rights reserved.

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et al. ■N -F un ctionalization o f the Tetrahedrane Fe 2 (C O ) 6 (//-S N H )

M. H erberhold

R,R'M

\ N ------S

/ ,X

\

(OC )3Fe ______ _ Fe( CO)3 3. 4. 5

A tßu,A s

\

R

R'

Si

Me

Me

3b

Si

Me

H

3c

Si

Me

‘Bu

3d

Si

Me

S iM e,

3e

Si

'Bu

H

3f

Si

Ph

’Bu

4

Ge

Me

Me

5a

Sn

Me

Me

5b

Sn

Et

Et

R,RM C1

N ------S

/X

M 3a

}

-er

,

-er \

6a

©

(

R

R

/ > v f

( p

PCI

N ------S

N ------S

-CI

(O C ),F c _ ------- _F e (C O )3

r °, As kÖ \

R

R

(OC)3F e _ ______ F e(C O )3 ^ \ t B u , A s C l

/X

\'

(OC)3Fe _____ _ Fe(CO)3

ASCI. f

R

N ------S

A X s>

(OC)3Fc ______ _ F e (C O )3

‘Bu

(C H ,),

R RBC I

7b

‘Bu

(C H ,),

-er

7c

'Pr

(C H ,),

7d

‘Pr

(S iM e ,),

6b

RR'B 8a

N ------S

/X c

(OC)3Fe ______ _ F e (C O )3

S c h e in e 1

\

7a

R

R

N'Pr,

N'Pr,

8b

N (B u )C H :C H :N B u

8c

N M e2

Fe

^ SiMe,SiMe2v^

sr > N

'

'

n —-

s

//W /x \\ (OC)3Ft------------Fe(CO)3 (OC)3Fe-------------Fe(CO )3 9

CISiMe2SiMe2Cl

-2CI"

° Nc > s

2 /^ \N (OC)3F e—--------- Fe(CO)3 ClSiMe2CH2CH2SiMe2Cl

ClSiMe2OSiMe2Cl

-2 CI'

-2 C r

^ SiMe2CH 2CH 2SiMe^

^ SiMe,OSiMe,^ S - —- N

// X

S ----- N

N ----- S

\

/ X

o

/ / V

(OC)3Fe------------Fe( CO )3 (OC )3Fe - ---------- Fe(CO)3

----- S

\

/X

(OC)3Fe------------Fe(CO )3

11

10 Scheine 2

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\-

(OC) 3Fe------------Fe(CO)3

M. H erberhold

et al. • N -F unctionalization o f the Tetrahedrane F e 2 (C O ) 6 (//,-SN H )

Table I. I5N, 2ySi and 31P NMR data of the tetrahedranes 3 and 7 (chemical shifts [ppm], coupling constants [Hz], solvent: CaD^, 25°C).

b'5N 3a 3b 3c 3d

-359.2 -370|al -371.0 -362.1

3e 3f

-374,0

), 32.1 (SiM ei) 30.8 9.8

[d] ] (7b) (1 g in C7DS, -20°C.

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M. H erberhold

et al. ■N -F un ctionalization o f the Tetrahedrane Fe 2 (C O ) 6 (^ -S N H )

Table II. Selected bond lengths |pm] and angles [°J in [Fe2(CO)6(//-SN-SiM e 2CH 2‘'-)]2 (11). S -N Fe( 1) - Fe(2) Fe( 1) - N F e(2 )- N F e(1)- S F e(2 )- S N -S i F e ( l) - C ( l) F e(1 ) - C(2) F e(1 ) - C(3) F e (2 )- C(4) F e(2 )- C(5) F e (2 )- C(6) Si - C(7) C(7) - C(7A) C (l) -0 ( 1 ) C(2) - 0 (2 ) C (3 )- 0 (3 ) C(4) - 0 (4 ) C(5) - 0 (5 ) C (6 )- 0 (6 ) Si -C (8) Si - C(9)

169.2(3) 250.6(1) 194.8(3) 194.4(2) 219.8(1) 220.7(1) 178.5(3) 179.5(4) 179.3(3) 180.8(3) 180.2(4) 180.2(4) 179.7(3) 186.5(3) 154.3(6) 113.6(5) 113.7(4) 113.2(4) 112.6(5) 113.1(5) 113.7(4) 185.2(3) 185.5(3)

Fe( 1)- S - Fe(2) Fe( 1) - S - N Fe(2) - S - N Fe( 1) - Fe(2) - S Fe(2) - Fe( 1 )- S N - Fe( 1) - S F e(l) - N -Si Fe(2) - N -Si S - N - Si C(8) - Si - C(9) Si - C(7) - C(7A) Fe( 1) - N - Fe(2) Fe( 1) - N -S Fe(2) - N -S Fe( 1) - Fe(2) - N F e (2 )- F e(l) - N N - Fe(2) - S N - Si - C(7) N - Si - C(8) N - Si - C(9) C(7) - Si - C(8) C(7) - Si - C(9)

69.4( 1) 58.4( 1) 58.0(1) 55.1(1) 55.5( 1) 47.7(1) 134.3(1) 138.9(2) 129.1(1) 112.7(1) 116.3(4) 80.2(1) 73.9(1) 74.4( 1) 50.0(1) 49.8(1) 47.6(1) 108.8(1) 103.4(1) 107.4(2) 112.6(2) 111.5(1)

hood to an ammonium-type nitrogen atom causes deshielding for 29Si [6, 7], and also for 11B [ 11 J ,31P [12], and ll9Sn [13]. A comparison of the relevant data for compounds 3, 5, 7 and 8 shows the same trend. Therefore, the bonding situation at the nitro­ gen atom corresponds to that of an ammonium-type nitrogen, at least as far as the element-nitrogen bond is concerned. The