Phosphorus-Substituted Ammonium Salts
FULL PAPER
tion of 2 equivalents of HCl (5.0 ml; 5 mmol HCl of a 1 solution
equivalents of H2O (21 mg; 1.18 mmol). After 15 min the colourless
in diethyl ether) in toluene (20 ml). After 4 d the resulting colour- precipitate of 12 was collected by filtration, washed with diethyl
less crystals were filtered off. Yield 1.15 g (98.1%).
ether (5 ml), and dried in vacuo. Yield 0.48 g (88.4%), m.p.
166°C (dec.).
Decomposition of 6; Formation of 1 and 7: A solution of 5 (1.0
g; 2.5 mmol) in toluene (20 ml) was treated with gaseous hydrogen
chloride for (ca.) 2 min but the precipitate (6) formed instan-
Triphenylmethylphosphonous NЈ,NЈ,NЈЈ,NЈЈ-Tetramethylguanidi-
nide (13): To a solution of 1.3 g (3.1 mmol) of 2 in 20 ml of diethyl
taneously was found to be dissolved again after prolonged action ether 0.2 g (5.3 mmol) of LiAlH4 were added at 0°C with stirring.
of HCl. This solution was heated in a sealed tube for 18 h at 80°C.
The solvent was removed in vacuo and the products were charac-
terized by 31P NMR spectroscopy. The data were identical to those
The mixture was allowed to warm up to room temperature and
stirring was continued for another hour. The reaction was
quenched by addition of water (20 ml), using a water bath for cool-
ing. The precipitate was filtered off and the solvent was removed
from the filtrate in vacuo. To the residue 10 ml of diethyl ether was
added and the product was obtained as a colourless amorphous
substance, containing small amounts of Ph3CH (4%), on cooling
this solution to Ϫ20°C. Yield 0.81 g (67.8%); m.p. 118°C (dec.). Ϫ
1H NMR: δ ϭ 2.55 [s, 12 H, N(CH3)2], 7.25 (s, 15 H, Ph3C), 5.67
of 1 and 7[19]
.
[tert-Butylphosphonic Bis(NЈ,NЈ,NЈЈ,NЈЈ-tetramethylguanidinide)]
· 2 HCl (10): Addition of 2 equivalents of HCl (4.52 ml of a 1
solution in diethyl ether; 4.52 mmol) to a stirred solution of 9 (0.75
g; 2.26 mmol) in toluene (20 ml) at room temperature resulted in
a yellow oil. After decanting the solvent the oil was washed with
n-hexane (2ϫ 10 ml), was dried in vacuo and 10 was obtained as
a colourless solid. Yield 0.89 g (97.3%); m.p. 79°C (dec.). Ϫ 1H
1
(d, J(PH) ϭ 188.4 Hz, 1 H, PH).
[Triphenylmethylphosphonous NЈ,NЈ,NЈЈ,NЈЈ-Tetramethylguanidi-
NMR: δ ϭ 1.42 [d, 3J(PH) ϭ 18.72, 9 H, PC(CH3)3], 3.21 [s, 24 H, nide]·2 HCl (14): To a solution of Ph3CPH(TMG) 13 (0.6 g; 1.5
N(CH3)2], no resonance for N(H)ϭC< was observed. Ϫ 31P NMR: mmol) in 10 ml of toluene were added at room temperature 3 equiv-
δ ϭ 31.70 (s). Ϫ FAB-MS chemical ionization with nitrobenzyl
alcohol (ϭ NBA)]: positive m/z (%): 666 (2) [(tBuP(ϭ
alents of HCl (4.5 ml of a 1 solution in diethyl ether; 4.5 mmol
HCl). The precipitate was filtered off and the product was obtained
O)(TMG)2·H)2]ϩ, 333 (78) [tBuP(ϭO)(TMG)2·H]ϩ, 218 (100) as a colourless solid. Yield 0.51 g (71.6%); m.p. 145°C (dec.). Ϫ
[tBuP(ϭO)TMG]ϩ, 71 (12) [HNCNMe2]ϩ; negative (m/z) (%): 188 1H NMR: δ ϭ 2.84 [s, 12 H, N(CH3)2], 7.09Ϫ7.43 (m, 15 H, Ph3C),
˜
(100) [ClϪ·NBA]Ϫ.
Ϫ
IR (KBr):
ν
ϭ
1253 (PϭO).
Ϫ
5.81 [dd, 1 H, J(PH) ϭ 235.6 Hz, J(HH) ϭ 4.6 Hz, P-H], 7.99 (m,
1 H, NH), 10.60 (s, 1 H, HCl2Ϫ). Ϫ C24H30Cl2N3P (462.4): calcd.
C 62.34, H 6.54, N 9.08; found C 62.49, H 6.52, N 8.96.
C14H35Cl2N6OP (405.35): calcd. C 41.48, H 8.70, N 20.73; found:
C 41.60, H 8.73, N 20.46.
tert-Butylphosphonic Bis(NЈ,NЈ,NЈЈ,NЈЈ-tetramethylguanidinide)]
Decomposition of 14: A 60 mg (0.13 mmol) sample of 14 was
·(p-Tol)SO3H (11): A solution of a mixture of 9 (0.45 g; 1.35 dissolved in CDCl3 (0.5 ml) and placed into a 5-mm NMR tube,
mmol) and p-toluenesulphonic acid (0.25g; 1.31 mmol) in 10 ml of
capped with a rubber septum. The decomposition was monitored
toluene was stirred at room temperature for 16 h. The oily precipi-
by 31P NMR; it was complete after 18 h. Product 15 was charac-
tate formed was separated from the solvent and after washing with terized by comparison of its H and 31P NMR data to those of an
1
n-hexane (two 5 ml portions) 11 was obtained as a colourless solid.
authentic sample[30]
.
1
Yield 0.62 g (94.5%); m.p. 135°C (dec.). Ϫ H NMR: δ ϭ 1.23 [d,
[Diphenylphosphinous NЈ,NЈ,NЈЈ,NЈЈ-Tetramethylguanidinide]
·
3J(PH) ϭ 16.85, 9 H, PC(CH3)3], 2.31 (s, 12 H, MeC6H4-
SO3Ϫ), 2.98 [s, 12 H, N(CH3)2], 7.10/7.74 [m (AAЈXXЈ), 4 H,
MeC6H4SO3Ϫ]. Ϫ 31P NMR: δ ϭ 20.28 (s). Ϫ FAB-MS (NBA):
positive m/z (%): 333 (86) [tBuP(ϭO)(TMG)2·H]ϩ, 218 (100)
tBuP(ϭO)TMG]ϩ, 71 (14) [HNCNMe2]ϩ; negative (m/z) (%): 324
HCl (17): A solution of 16 (0.61 g; 2.01 mmol) in toluene (30 ml)
was treated with gaseous hydrogen chloride until precipitation of a
colourless solid commenced. The solid product was separated by
filtration and investigated by 31P- and 1H-NMR spectroscopy. The
spectra indicated a mixture of 17 and HTMG·HCl. In the 31P-
NMR spectrum of the filtrate a signal was observed which was due
to Ph2PCl [δ(31P) in C6D6 ϭ 82.2[35]]. Ϫ 1H NMR: δ ϭ 2.98 [s,
12 H, N(CH3)2], 7.12Ϫ7.79 (m, 5 H, C6H5); no resonance for
(16) [MeC6H4SO3·NBA]Ϫ, 171 (100) [MeC6H4SO3]Ϫ.
Ϫ
C21H37N6O4PS (500.60): calcd. C 50.39, H 7.45, N 16.79, S 6.40;
found: C 50.02, H 8.07, N 16.53, S 6.21.
[Chloro Triphenylmethylphosphonous NЈ,NЈ,NЈЈ,NЈЈ-Tetramethyl- N(H)ϭC< was observed. Ϫ 31P NMR: δ ϭ 41.2 (s).
guanidinide] · HCl (12): Ϫ Method A : Treatment of 5 with Phos-
Bis(NЈ,NЈ,NЈЈ,NЈЈ-tetramethylguanidino) Triphenylmethyl Phos-
gene: A solution of C(ϭO)Cl2 (0.27 g; 2.7 mmol) in toluene (1.4
phonium Chloride (19): NЈ,NЈ,NЈЈ,NЈЈ-Tetramethylguanidine (2.0 g;
ml) was added to a solution of 5 (1.1 g; 2.7 mmol) in toluene (20
17.4 mmol) was added dropwise with stirring over 10 min at room
ml) at room temperature. After 10 min the evolution of CO2 had
temperature to a solution of 1 (2.0 g, 5.80 mmol) in 20 ml of di-
ceased, and the solid product was separated and washed with di-
chloromethane. After stirring for 0.5h at room temperature the re-
ethyl ether (10 ml). The product was dried in vacuo and the product
action mixture was washed with water (10 ml) and was cooled to
was obtained as an amorphous solid. Yield 1.0 g (80.0%); m.p.
0°C. The dichloromethane layer was separated from the mixture
168°C (dec.). Ϫ 1H NMR: δ ϭ 2.95 [s, 12 H, N(CH3)2], 7.13Ϫ7.41
and dried over Na2SO4 (5.0 g). The solvent was removed in vacuo,
(m, 15 H, Ph3C), 7.85 (s, 1 H, NHϪ ). Ϫ C24H28Cl2N3P (460.4):
and the residue was washed with 10 ml of diethyl ether, resulting
calcd. C 62.61, H 6.13, N 9.13; found: C 62.80, H 6.29, N 8.94.
in a colourless, amorphous substance. Yield 1.59 g (50.9%); m.p.
Method B: Treatment of 2 with HCl: To a solution of 2 (1.0 g,
2.36 mmol) in 10 ml of toluene was added at room temperature 1
146°C (dec.). Ϫ 1H NMR: δ ϭ 2.70 [s, 24 H, N(CH3)2], 7.05Ϫ7.25
(m, 15 H, Ph3C), 8.23 [d, 1J(PH) ϭ 471.5 Hz, 1 H, PH]. Ϫ 31P
equivalent of HCl (2.36 ml of a 1 solution in diethyl ether; 2.36 NMR: δ ϭ 5.1. Ϫ C29H40ClN6P (539.1): calcd. C 64.61, H 7.48, N
mmol HCl). After 5 min the colourless precipitate of 12 was col-
lected by filtration, washed with diethyl ether (5 ml), and dried in
vacuo. Yield 1.0 g (91.7%), m.p. 167°C (dec.).
15.59; found C 62.19, H 7.63, N 14.24.
[Triphenylmethylphosphonous Bis(NЈ,NЈ,NЈЈ,NЈЈ-tetramethyl-
guanidinide)] HCl (20c): To solution of [Ph3CPH-
(TMG)2]ϩClϪ (19) (0.5 g; 0.93 mmol) in 10 ml of dichloromethane
·
3
a
Method C: Via Hydrolysis of 2: To a solution of 2 (1.0 g; 2.36
mmol) in 10 ml of toluene were added at room temperature 0.5 were added at room temperature 3 equivalents of HCl (2.8 ml of a
Eur. J. Inorg. Chem. 1998, 865Ϫ875 873