Intramolecular rearrangements in phosphoranes via bimolecular intermediates

INTRAfllOLECULAR

IN

REARRANCEIIIENTS

Roller

Graduate

(Received

School

The intramolecular oua authora 16 hare that the

the

procaaa

atataa

bean abla

molecular

rachaniama,

molecular

rearrangement

mant.

Thia would aarva

Pirat

prooP oP the

ana,

RPF4, although

six-coordinate

Praa energy

would

butaa

the

to aarantially

at laaat

ia

aquara

unreliability

pyramid

doaa

complex,

both OP rrhich could

with

product,

higher

oP the method aray

rode.

a bi-

raarrangathe

a Pluorophoaphor-

to all

known phoaphoranaa.

Laria

TEP.

oP

and provide

acid

can

and can Corm atabla Pirat

the

that

11 each

CNDO/P calculationa geometry.

I,

Only when mora

activated

by only

RPF4,

than dacompoaa to I’,

corplax

CND0/2 calculationa’

than the

uni-

lxplicitly

or back to I itaa1P.

Prom equilibrium

ProoP

raarrangamant

We ewggast

dimar would ba excited out Purthar

Experiment

in Pavor oP the m

dimar II go to IV, via

liaa 30koal

atataa.

the sxs

II which

Recant

a dimar oP

UPR1*3 and TR* m

appliaa

iona.

intermediate

the

We have not carried

excited

We diacuaa

ia a atrong

by Comlay. 6,7

the

involving

an mxm

and negative

by numarUIa luggaat

uniaolacular.

Pavorad

argument8

19 February 1973)

, either

evidence

axcluda

phoaphorua(V)

dimaric

-12kcal

atrong

one oP the

complaxaa

availabla

the

involved.

Barry paaudorotation)

a reasonable

auggaation.

provide

is

aa mataatabla

aaaociatad

and than to V as poatulatad that

or more likely

N.Y. N.Y. 10033

haa bean diaouaaad

procaaa

a phoaphorana-aalvant

and rachaniame

that

Univaraity,

be bimolecular

between

neutral

(e.g.

the

that

INTERUEDIATES

in UK for publication

to distinguish’

can Porm the mprmaatric the m

actually

ataraochamiatry

It ia mall-known

Yaahiva

oP phoaphoranaa

aaauma

or involving

aa tranaition

haa not yet

might

BIftlOLECULAR

Illuahar

received

rearrangement

who invariably

phoaphorana

occur

oP Science,

in USA 17 January 1973;

VIA

PHOSPHORANES

Jaramy I.

Printed in Great Britain.

Pergamonheas.

TetrahedronLetters No. 15, pp 1093 - 1096, 1973.

have

Ckcal

aupporting

because Notice

ahomn

bridge

P...F

that

III,

oP the

oontriour known

our diaoua-

No.

1094

aion

solarhat

is

tions

for

the

sinplifiad A-proupe

in and

that

that

thmre

I and

I’

are

actually

arm not

oeuoral

produced

in

non-•quivalont aqua1

loca-

concentration.

2

FA I ,F---kR

---F/I R-P F’ ’ Q

F

$F

1 F I,F’PLR R-P-F/I F’; F

z C4

F

m

II

FA’

F 1 /FA’

1 ,F’

+

R-P

R-P.

I’F

2

FA

R-P,

:I

b ’ YF I

F”

FA P

We further I can I’

or

form

the

back

COlnp1oXas,

excited

to 9

suggest

it

I.

is

Since likely

that complex

in

the

VI which

triethylamine that

presence

many

can and

other

OP appropriate also

decompose

diethylether

solvmts

‘IF

to

actually

should

FA R-

solvents

P---solvent

the

either

the

form

at least

pho8phormnm roarranped

atablo

form

ouch

lom-lying

13

1095

MO. 1;

excited complexes. erature

is

Unfortunately,

sufficiently

lee

tha

that

it

solubility

mill

be

of

phosphoranss

exceedingly

at

difficult

lor

to

trp-

do

ths

experiments mith non-interacting solvents.

necessary These

mechanisms

are

attractive

because:

(1) they provide one of the tro possible stereoepscific rsarrangemants consistent

mith

5

experiment;

they utilize known octahedral

(2)

phosphorus

lative tetragonal pyramid of which there are dimer and

has the

against

no

geometry

known

rather

exasplee;

than

an

the

exampla

apocu-

of

ths

been proposed for the molecular structure of (C13CH)2[(C,H,)~PC12]2,

related

SbFS

polymeric even in solution.

is

non-symmetric

dimers

(C6H5)21Cl and probably SF4

since are

other

hypervalent

call-known

to

have

they

should

be

no

preJudice

molsculss

such

as

RrF 11

structure.

analogous

12 sxamples in metals occur for hexacoordinate iron, (3)

There

and

explain the wide range of sctivation

tetracoordinate

snergies

3’

ClF 3’

Rslsted

platinum.

13

since the

obtained,

barrier to diner-formation eill depend critically on the molecules involved ss is 14 activation generally the case in transitional metal complexes; the observed energies (AlI+)for RPF4 Nlkcal Ilk to a

ths

molecules

are

for R-Cl, and 5 4kcal for have same

ssauned

hare

mechanism.

that

all

A non-TEP

>

R=F

llikcalPor and

CH

3’

phosphoranes structure

are

has

been

TSP’s

are

therefore

not

intended

to

be

and

recently

recent kinetic study has indicated the possibility of

assumptions

their

generous

support.

according

rearrange found,

an s

S

process.

horsver, l6

Such

17 all-exclusive.

I am grateful to A.H. Comley for valuable discussions ONR for

9kcal for RmN(CH3)2,

R=NH2, l5

snd

to

thm

NSF snd

and

No. 13

1096 Ret’encea 1. K. Niisloe,

Account8

2. F. Aemirez,

3. F.H.

4. A. Schautzler 5. J.I.

J.

6. T.A. Furtsch,

Treichel, believed chel

Am. Chem. Sot.

(Inorg.

Chem. 1,

P.

of PF2(Nllle2)

with

and I.

Ugi,

9. L. Lunazzi

Hoffman,

Anger.

H.

Chen.,

G.G. Arzoumanidis,

11.

2.1. Musher,

12. G.R. Davies,

in

in HPF4

and

(J.

has

H2PF3

5759 (1970).

found

by P.m.

2017 (1967))

Goodrich

CH3PF3H and C2H5PF3H.

92,

been

Am. Chem. Soc.89, and by R.A.

The

and P.M.

but

Trei-

reaction

+ NCPf3(Nme2)

Chem. 1,

Klusacek,

Internat.

2067 (1968))

0.

Edit.

J.

is

likely

to take

place

magnetic

marquarding,

lo, Res.

5.

Pfohl,

F.

Ramirez

687 (1971). 1,

119 (1969).

Chem. Comm. 217 (1969).

Angew.

Chem. Internat. Ed. 5, 54 (1969).

R.H.B.

IIlaue,

P.C.

13. B.T. Kilbourn and R.H. mais, 14.

NY.1967.

NCPF2(Br)(Nme2).

and S. Broanstein,

10.

J. Am. Chem. Sot.

BrPF(NMe2)

a dimer

Acsdemic,

Cosley,

Pierce

694 (1968))

Inorg.

P.

2, Ed. V. Gutmenn,

catalyzes,

and K. Cohn,

Gillespie,

A.H.

and S.6.

BrCN 3

+

70 (1968).

5662 (1972).

exchange

Clone

(J.E.

6.

end

I, Vol.

94,

to be HP end impurity

PF2(NIAe2)

via

Dierdorf

Goodrich

168 (1966).

Chemistry

intermolecular

R.A.

1,

Chem. Ras.

Helocen

D.S.

for

;2, 321 (1970).

Chem. Res.

Accounts in

musher,

7. Evidence

Chem. Aes.

Accounts

Wostheimer.

and Footnotes

G. 111.Whiteeides

and H.L.

Omston

and

P.T. Thompson, J.Chem.Soc.A1251(1968).

Chem. Comm. 1507 (1968).

mitchall, J. Am. Chem. Soo. a,

53B4 (1969) and the

Ph.D. thesis of H.L. mitchell, I.I.T. 1969. 15. A.H. Cowley end 16. A. Kleibe,

J-F

J.R.

Brazier,

Schweiger, J.C.S.Chem.Comm. 560 (1972). F. mathis

and R. Wolf, Tetra.Lettars 42 4367, (1972).

17. J. I. Illusher in Conformational Analvsfs, Academic, NY (1971) pp 177-189.