First synthesis of pentacoordinated phosphirenes

'oo404039/90 $3.00+.00 PcrguMnResl plc

Tet~&dmnLenem. Vo131.No.24,pp3429-3432 1990 F'rintedinGreatBritain

Hichael Fachbereich

FIRST

SIITHESIS

Ehle,

Oliver

OF PEITACOOBDIllATED

Vagner,

PHOSPHIBEIES1

Uwe BergetrHger,

and Hanfred

Begits*

Erwin-SchrLSdlnger-Strafle, Kaieeralautern, Federal Republic of Germany

Chemie der UniveraitPt D-6750 Kaieerelautern,

8a-d react with tetrachloro-oAbstract: 1-Ralo- and 1-cyano-lg-phoaphirenes --to furnish the previously addition at phosphorus quinone (2) by oxidative atom in the pentacoordinated unknown title compounds lOa-d. The chlorine phosphirene z undergoes nuclyophilic exchange reactions yielding -lOc-e.

lg-Phosphirenes

were

first

prepared

in 1982

as the

chromfum

or tungsten

carionyl complexes (&; P+Cr(or W)(CO)5 in place of P) by Mathey and coworkers . Since then, the complexes as well as the metal-free compounds A the;selves have found many uses in the syntheses of organophoephorua compounds . On the other tence

hand,

there

was

previously

of the pentacoordinated

The

products

from

no conclusive

phosphirenes

the retctions

evidence

for the exie-

2.

of PhSP

with

CEC15/t-BuOK

and aldehydes

were assigned the structure 2 , but are almost +certainly th5e isomeric alkynyl(trlphenyl)phosphonium chlorides (Ph3P-CZC-R) Cl- (Ref. ). The existence 5 of the type 4, which were claimed to be formed by [2+1]of X -phosphirenes with pkenylor alkoxyacetycycloaddition reactions of trlbutylphosphine lenes6 from

is

the

open-chain mature

in

synthesis

equally in eitu

uncertain. reactions

vinylphosphonium the

absence

of

The

of

assumption

the products

salts

like

spectroscopic

of an unambiguously

of with

a

i -phosphirene

electrophiles

(Bu,,P-CP;(or evidence

characterized,

. We

RX

OR)=CHR)+ now

pentacoordinated

structure to furnish

Cl-

report

is the

prefirst

phosphirene.

Starting materials for the synthesis of 10 are the lg-phoephirenes 8a-d; & had previously been prepared by us from 2 and chlorophenylcarbene (GnTrated thermally from the diazirine &). The 2g-phoephirene & is ,certainly formed initially and then undergoes a 1,3-chlorine shlft8to yield 8a . 9analogously The 1-fluoro-lg-phosphfrene 8b was prepared from 5 and 6b 10 (160 'C, under pressure, Schlenk tube, bulb-to-bulb . The lgdi~tillat~n) phosphlrenes & and 8d were obtained directly by nucleophilic exchange of the chlorine in k bromousing and cyar;trimethyleilane (excess, 20 OC, separation by distillation), respectively .

3429

3430

t-Bu [1,31-xPh.

k

8

”

t-By ’

1 -

The

’ Ph bP

b:X=Fl

increase

e:

in the coordination

8c

at phosphorus

was

realized

by reaction

of 8a-d with tetrachloro-c-quinone (9_) in ether (if necessary in a gas pressurFvYsse1, Table 1). Products c, 2, & were obtained as colourless crystals while E separated as a colourless oil. Similar to the Ill-phosphirene &, the chlorine atom in the pentacoordinated phosphirene 10a can also be nucleophilically at room exchanged temperature (albeit rnx slowly) by treatment with bromo- and cyanotrimethylsilane to furnish &, A; the azide group in c can be introduced in an analogous manner. The carbon atoms of the three-membered ring (Ph-2: 6 - 163.4-171.3; tBu-C: small

6 - 171.6-180.0), 3 J(C,H) couplings

which

field

and can thus be compared

in

Table 1. Reaction conditions, phosphirenes lOa-e. Product

Reaction

can

the

with

(R - Cl) E

recognized

those

purification,

conditions

(purification) LOa

be

proton-coupled

readily

spectra,

of cyclopropenylium yields,

on

account

appear

at

salts.

and NMR data

of

rather

Electron

5 for the X -

Yield

31P-NMRa

13C-NMRb

[Xl

6 [ppml

f-Bu-2

6 [ppm] Ph-2

ether, 7 h, 40-45 'C (from CR2C12 at -78 'C)

31

-82.2

178.8 (21.7)

169.2 (11.7)

ether, (MPLC,

-69.8'

176.3 (35.6)d

166.6 (25.2)d 171.3

10 h, 40-45 'C etherjhexane)

25

(R = P) 1oc (xBr)

ether, 0.5 h, 25 'C (f rom ether at 25 'C)

27

-106.3

180.0 (16.8)

10d (x-

ether, 7 h, 35-40 'C (from hexane at +7 'C)

72

-126.6

171.6 (26.0)

(4.9) 163.4 (14.6)

-85.4

175.9 (25.1)

165.4 (15.1)

CN)

* (R - N3)

excess Tms-N 3, 25f0Ce (no purification)

lOOf

the low

85% phosphoric acid as extrrnal standard. THS as internal standard, J_(P,C) coupling [Hz] in brackets. = 1108 Hz. = 8.5 (t-Bu-2) or 10.3 Hz (Ph-2). Ttansformation of E to 1Oe. f) Removal of volatilee undervacuum (l~lO_~ mbar) furnishes 1Oe.

3431

iransfers according to fif--)~f--)~ could explain this phenomenon. The J(P,C) couplings of the respective carbon atoms are markedly smaller than 7,ll . Au increase of the coordination at phosthose of the lg-phosphirenes 1 phorus by one only through corplex formation has the same result. A crystal structure analysis performed on E confirmed the constitution of the pentacoordinated phosphirene. A highly distorted, square pyramidal arrangement

at phosphorus

ring

the

and

carbon

atom

oxygen

occupies

was

atoms

found; of

the apex

the

two carbon

the o-quinone

form

atoms the

of the three-membered base

while

the

Selected angles Pl-02

bond

lengths

[O]: Pl-01 1.700(3),

1.709(4), Pl-c4

Fig.1.

1.715(4),

1.784(4),

Ol-c5

02-C6

1.351(S),

1.126(6),

1.360(6), Ol-Pl-02 140.4(2), Ol-Pl-c4 104.1(2), 02-Pl-C3 97.3(2), CZ-Pl-C4 108.2(2).

C2-C3

CS-C6 1.374(6). 90.3(l), Ol-Pl-c2 Ol-Pl-C3 104.4(2), 102.0(2), 02-Pl-c2 02-Pl-C3 146.8(2), 146.8(2), 02-Pl-C4 CZ-Pl-C3 46.8(2), 112.3(2), C3-Pl-C4

Crystal

selected

structure

structural

of the 1'-phosphirene The

intracyclic

the

markedly

comparatively

short

distances

in the

three-membered

lengthened

C/C

P/C

[1.790(4)

bonds

double

bond and

ring

[1.360(a)

1.715(4)

[Al and

1.668(3),

Pl-c2

Pl-c3

1.371(S), Nl-C4

note:

cyanide

(Fig. 1).

I]

unit A] as

and

parameters fi13.

are worthy as

well

compared

of

as

the

to

the

corresponding bonds in e fi [1.303(S) It, 1.784(4) and 1.781(4) All4 or in if% again emphasize the importance of the ylide triphenyl-lg-phosphirene structures z, s for the description of the pentacoordinated phosphirene.

3432 Acknowledgements: We thank the Deutsche Porschungsgemeinschaft and the Fonda der Chemischen Industrie for financial support. M. Ehle thanks the State Government of Bheinland-Pfals for a graduate grant. We are particularly grateful to Professor F. Mathey for numerous fruitful discussions both in Kaiserslautern and in Palaiseau. References

and Notes

1. Phosphorus

compounds

with unusual

coordination;

Part

44. For Part

43,

see: Annen, U.; Begite, M.; Kluge, H. Chem. Ber. 123 (1990) in press. 2. Marinetti, H.; Mathey, P.; Fischer, J.; Mitschler, A. J. Am. Chem. Sot. 104 (1982) 4484. 3. Review: Mathey, F. Chem. Rev. 90 (1990) in press. 4. Kansal, N. M.; Verma, S.; Mishra, R. S. ; Bokadia,

M. H. Indian

J. Chem.

E (1980) 610. Kansal, N. M.; Verma, S .; Bokadia, M. N. Indian J. Chem. E (1980) 611. Verma, S.; Kansal, N. M .; Mishra, R. S.; Bokadia, M. M. Heterocycles E (1981) 1537. Kansal, N. M.; Verma, S.; Mishra, R. S.; Bokadia, M. M. Acta Cienc. Indica. [Ser] Chem. i (1982) 239. 5. For critical evaluation and new interpretation, see Ref. . 6. Torgomyan, A. M.; Ovakimyan, M. Zh.; Indshikyan, M. G. Arm. Khim. Zh. 32 (1979) 288.; C. A. 92 (1980) 6622a. Torgomyan, A. M.; Pogosyan, A. S.; Ovakimyau, M.Zh.;zdshikyan, M. G. Arm. Khim. Zh. 33 (1980) 408; C. A. 93 (1980) 186471~. Gosparyan, G. Ts.; Minasyan, G. G.; Torgomyan, A. M.; Ovakimyan, M. Zh.; Indshikyan, M. G. Arm. Khim. Zh. 36 (1983) 456; C. A. 100 (1984) 103459u. Minasyan, G.G.; Torgomyan, A. M.; Ovakimyan, M. Zh.; Indehikyan, M. G. Arm. Khim. Zh. 2 (1985) 204; -C. A. 104 (1986) 19636s. 7. Wagner, 0.; Ehle, M.; Regitz, M. Angew. Chem. 101 (1989) 227; Angew. Chem. Int. Ed. Engl. E (1989) 225. 8. Becker, G.; Greaser, G.; Uhl, W. 2. Naturforsch. B36 (1981) 16; improved procedure: Reach, W. Hees, U.; Regits, M. Chem. Ber. 120 (1987) 1645. 9. Moss, R. A.; Terpinski, J.; Cox, D. P.; Denney, D. 2.; Krogh-Jospersen, K. J. Am. Chem. Sot. 107 (1985 2743. 1 31P-NMB (CDC13): 6 - -48.4 (d, J(P,F) - 993 Hz); "F-NMR 10. 2: (CDC13, 31P-NMR (CDC13): 6 C6F6 int. '$1.): 6 - 17.0 (d, lJ(P,P) - 993 Hz). &: -61.4. 8d: P-NMR (CDC13): 6 - -232.4; IR (KBr): v - 2145 cm-l (CrN). 11. a) Mariztti, A. Mathey, P. J. Am. Chem. Sot. 107 (1985) 4700. b) Marinetti, A.; Mathey, F.; Fischer, J.; Mitschler, A. J. C. S. Chen. Commun.

1984, 45. c) Deschamps, B.; Mathey, F. New. J. Chem. 12 (1988) 755. S.; Mathey, F. Organometallics 12. xnd, 1 (1988) 1796. 13. ClgH14C14N02P, monoclinic, space group: PZl/n, a = 8.812(2), b = - 14.146(4) A, B - 108.02(2)'-, T = 20 'C, 2 - 4, dcalc 17*511(5)llc 1.48 g'cm , Enraf-Nonius CAD 4 diffractometer, monochromatic MoKu irradiation, absorption 2705

3591

independent

correction

reflections

Atomic

[I > 20(I)]

coordinates,

data are available Crystallographic Road,

Cambridge

complete 14. Wagner.

reflections with 4.0 ( 2 8 5 50.0°, -1 cm ), complete matrix refinement

(p - 6.623 tables

on demand

Data

and 244 variables,

of bond lengths

Centre,

from

CB2 lEW, U.K. Rach

citation 0; Regitz,

the Director

University

R - 0.047,

and angles,

RW - 0.044.

and structural

should

Laboratory,

Lensfield

be accompanied

of this publication. M. unpublished

(ReceivedinGumany24April1990)

results,

with

of the Cambridge

Chemical

request

-

Kaiserslautern,

1989.

by the