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tracted by washing with Et2O (3100 mL), and the combined or-
ganic phases were washed with brine, dried over MgSO4, concen-
trated and filtered through a SiO2 plug (ø=6,5 cm3 cm). The sol-
vent was removed in vacuo and the crude products were used
without additional purification. There was one exception (see
below): tetrazolo[1,5-a]pyridine F (“2-azido pyridine”, see above)
was purified by column chromatography (SiO2, dichloromethane/
ethyl acetate 9:1 v/v).
C10), 36.0 (d, J(C,P)=15.5 Hz; tBu-C7), 116.1 (d, J(C,P)=8.3 Hz; Ar-
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C3, Ar-C6), 147.8 (d, J(C,P)=11.4 Hz; Ar-C2), 152.1 (s; Ar-C4, Ar-C5),
199.8 ppm (d, J=55.4 Hz; Ar-C1); 31P{1H} NMR (162 MHz, CD2Cl2):
d=174.7 ppm (s); HR-ESI-TOF-MS (+, 150.0 V): m/z calcd for
C10H13N4P [M+H]+: 221.0951; found: 221.0965; elemental analysis
calcd (%) for C10H13N4P: N 25.44, C 54.54, H 5.95; found: N 25.76, C
54.41, H 5.84.
Compound 4a: White crystalline solid (715.21 mg, 3.26 mmol,
87%); 1H NMR (400 MHz, CD2Cl2): d=1.49 (d, 4J(H,P)=1.5 Hz, 9H;
Me-H9, Me-H10, Me-H11), 7.42 (m, 1H; Ar-H5), 7.48 (m, 2H; Ar-H4,
Ar-H6), 7.76 ppm (m, 2H; Ar-H3, Ar-H7); 13C NMR (176 MHz, CD2Cl2):
d=31.8 (d, 3J(C,P)=7.6 Hz; Me-C9, Me-C10, Me-C11), 35.9 (d,
2J(C,P)=16.2 Hz; tBu-C8), 122.8 (d, 3J(C,P)=7.3 Hz; Ar-C3, Ar-C7),
Compound 1a
Tetrazolo[1,5-a]pyridine (450.0 mg, 3.75 mmol, 1 equiv) was added
to
a
solution of (2,2-dimethyllidyne)phosphine (412.9 mg,
4.13 mmol, 1.5 equiv) in toluene (30 mL). The reaction mixture was
heated for 1 week at T=808C. After full conversion of the starting
material, the solvent and excess (2,2-dimethylpropylidyne)phos-
phine were removed in vacuo. The crude product was redissolved
in toluene at RT and crystallised by slow cooling to T=À208C.
Compound 1a was obtained as slightly yellow needles (437.7 mg,
1.99 mmol, 53%). 1H NMR (400 MHz, CD2Cl2): d=1.48 (d, 4J(H,P)=
1.6 Hz, 9H; Me-H9, Me-H10, Me-H11), 7.31 (ddd, 3J(H,H)=7.5 Hz,
3J(H,H)=4.9 Hz, 4J(H,H)=1.1 Hz, 1H; Ar-H5), 7.88 (td, 3J(H,H)=
7.8 Hz, 4J(H,H)=1.9 Hz, 1H; Ar-H4), 8.08 (dt, 3J(H,H)=8.3 Hz,
4J(H,H)=1.0 Hz, 1H), 8.44 ppm (ddd, 3J(H,H)=4.9 Hz, 4J(H,H)=
2
129.0 (s; Ar-C5), 130.1 (s; Ar-C4, Ar-C6), 141.6 (d, J(C,P)=10.4 Hz;
Ar-C2), 199.0 ppm (d, 1J(C,P)=55.5 Hz; Ar-C1); 31P{1H} NMR
(162 MHz, CD2Cl2): d=174.3 ppm (s); HR-ESI-TOF-MS (+, 200.0 V):
m/z calcd for C11H14N3P [M+H]+: 220.0998; found: 220.1013; ele-
mental analysis calcd (%) for C11H14N3P: N 19.17, C 60.27, H 6.44;
found: N 18.59, C 60.06, H 6.46.
Compound 5a: White crystalline solid (776.39 mg, 3.30 mmol,
88%); 1H NMR (500 MHz, CD2Cl2): d=1.43 (d, 4J(H,P)=1.6 Hz, 9H;
Me-H), 5.69 (d, 3J(H,P)=6.8 Hz, 2H; CH2), 7.36 ppm (m, 5H; Ar-
H);13C NMR (176 MHz, CD2Cl2): d=31.9 (d, J(C,P)=8.0 Hz; Me-C10,
Me-C11, Me-C12), 35.7 (d, 2J(C,P)=16.2 Hz; tBu-C9), 56.6 (d,
2J(C,P)=13.0 Hz; CH2-C2), 128.9 (s; Ar-C5, Ar-C7), 129.0 (s; Ar-C6),
129.4 (s; Ar-C4, Ar-C8), 137.9 (d, 4J(C,P)=1.9 Hz; Ar-C3), 199.3–
198.2 ppm (d, 1J(C,P)=56.3 Hz; Ar-C1); 31P{1H} NMR (162 MHz,
CD2Cl2): d=171.4 ppm (s); HR-ESI-TOF-MS (+, 200 V): m/z calcd for
C12H16N3P [M+H]+: 234.1155; found: 234.1151; elemental analysis
calcd (%) for C12H16N3P: N 18.02, C 61.79, H 6.91; found: N 17.79, C
61.79, H 6.91.
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1.9 Hz, J(H,H)=0.9 Hz, 1H; Ar-H6); 13C NMR (176 MHz, CD2Cl2): d=
31.1 (d, 3J(C,P)=8.3 Hz; Me-C8, Me-C9, Me-C10), 35.3 (d, 2J(C,P)=
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15.3 Hz; tBu-C7), 113.4 (d, J(C,P)=2.6 Hz; Ar-C3), 123.5 (s; Ar-C5),
139.1 (s; Ar-C4), 148.5 (s; Ar-C6), 153.3 (d, 2J(C,P)=8.4 Hz; Ar-C2),
199.0 ppm (d, 1J(C,P)=57.2 Hz; Ar-C1); 31P{1H} NMR (162 MHz,
CD2Cl2): d=167.51 ppm; HR-ESI-TOF-MS (+, 150.0 V): m/z calcd for
C10H13N4P [M+H]+: 221.0951; found: 221.0967; elemental analysis
calcd (%) for C10H13N4P: N 25.44, C 54.54, H 5.95; found: N 25.36, C
54.56, H 5.97.
General synthesis procedure of 5-TMS-substituted triaza-
phospholes
General synthesis of compounds 2a–5a
Aryl and benzyl azides (3.75 mmol) were mixed with a stirring bar
in a 250 mL Normag flask. Subsequently, the azide was frozen and
the flask was evacuated, followed by the addition of dry [(trime-
thylsilyl)methylidyne]phosphine (ꢁ100 mL) in toluene (large
excess). The reaction solution was allowed to warm to RT and was
stirred for 24 h. The solvent and excess alkyne were removed in
vacuo.
Aryl and benzyl azides (3.75 mmol) were mixed with a stirring bar
in a 100 mL Normag flask. Subsequently, the azide was frozen and
the flask was evacuated, followed by the addition of dry toluene
(ꢁ50 mL) and (dimethylidyne)phosphine (412.9 mg, 4.13 mmol,
1.5 equiv). The reaction solution was allowed to warm to RT and
was stirred for 24 h. The solvent and excess alkyne were removed
in vacuo. The resulting solid was recrystallised from a hot saturated
solution in n-pentane.
Compound 1b: Orange oil (806.34, 3.41 mmol, 91%); 1H NMR
(400 MHz, CD2Cl2): d=8.49 (ddd, J=4.9, 1.8, 0.9 Hz, 1H; HAr), 8.14
(dt, J=8.2, 0.9 Hz, 1H; HAr), 7.95–7.89 (m, 1H; HAr), 7.35 (ddd, J=
7.4, 4.9, 1.0 Hz, 1H; HAr), 0.44 ppm (d, J=0.6 Hz, 9H; CH3); 13C NMR
(101 MHz, CD2Cl2): d=186.4 (d, 1J(P,C)=74.0 Hz; C=P), 153.6 (d,
Compound 2a: White crystalline needles (668.89 mg, 3.04 mmol,
81%); 1H NMR (400 MHz, CD2Cl2): d=1.51 (d, 4J(H,P)=1.5 Hz, 9H;
tBu), 7.47 (ddd, 3J(H,H)=8.2 Hz, 3J(H,H)=4.8 Hz, 4J(H,H)=0.8 Hz,
1H; Ar-H4), 8.12 (dddd, 3J(H,H)=8.2 Hz, 4J(H,P)=2.5, 4J(H,H)=
1.5 Hz, 5J(H,H)=1.0 Hz, 1H; Ar-H3), 8.65 (dd, 3J(H,H)=4.8 Hz,
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2J(P,C)=7.1 Hz; C2, Ar), 149.2, 139.8 (s; CAr), 124.2 (d, J(P,C)=1.1 Hz;
C4, Ar), 114.6 (d, 3J(P,C)=2.2 Hz; C3, Ar), À0.19 ppm (d, 3J(P,C)=3.8;
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4J(H,H)=1.5 Hz, 1H; Ar-H5), 9.03 ppm (dt, J(H,P)=2.3 Hz, J(H,H)=
CH3); 31P{1H} NMR (162 MHz, CD2Cl2): d=211.6 ppm (s).
1.0 Hz, 1H; Ar-H6); 13C NMR (101 MHz, CD2Cl2): d=31.2 (d, J(C,P)=
7.9 Hz; Me-C8, Me-C9, Me-C10), 35.4 (d, 2J(C,P)=15.5 Hz; tBu-C7),
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Compound 2b: Orange solid, (824.1 mg, 3.49 mmol, 93%). H NMR
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124.1 (s; Ar-C4), 129.4 (d, J(C,P)=6.0 Hz; Ar-C3), 137.5 (d, J(C,P)=
9.4 Hz; Ar-C2), 143.4 (d, 3J(C,P)=8.6 Hz; Ar-C7), 149.7 (s; Ar-C5),
199.0 ppm (d, 1J(C,P)=56.5 Hz; Ar-C1); 31P{1H} NMR (162 MHz,
CD2Cl2): d=170.9 ppm (s); HR-ESI-TOF-MS (+, 250.0 V): m/z calcd
for C10H13N4P [M+H]+: 221.0951; found: 221.0969; elemental anal-
ysis calcd (%) for C10H13N4P: N 25.44, C 54.54, H 5.95; found: N
25.50, C 54.51, H 5.89.
(400 MHz, CD2Cl2): d=9.14–8.99 (m, 1H; HAr), 8.66 (dd, J=4.8,
1.4 Hz, 1H; HAr), 8.17–8.12 (m, 1H; HAr), 7.48 (ddt, J=8.2, 4.8,
0.8 Hz, 1H; HAr), 0.45 ppm (s, 9H; CH3); 13C NMR (101 MHz, CD2Cl2):
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d=186.4 (d, J(P,C)=75.5 Hz; C=P), 150.3 (d, J(P,C)=1.2 Hz; C5, Ar),
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144.1 (d, J(P,C)=7.7 Hz; C3, Ar), 130.2 (d, J(P,C)=5.3 Hz; C4, Ar), 124.7
(s; C6, Ar), À0.21 ppm (d, 3J(P,C)=3.6 Hz; CH3); 31P{1H} NMR
(162 MHz, CD2Cl2): d=213.7 ppm(s); HR-ESI-TOF-MS (+, 330 V): m/z
calcd for C9H13N4PSi [M+Na]+: 259.0539; found: 259.1177.
Compound 3a: White crystalline needles (685.4 mg, 3.11 mmol,
83%); 1H NMR (500 MHz, CD2Cl2): d=1.51 (d, 4J(H,P)=1.7 Hz, 9H;
Compound 4b: Red oil (803.0 mg, 3.41 mmol, 91%); 1H NMR
(400 MHz, CD2Cl2): d=7.82 (dt, J=8.4, 1.2 Hz, 2H; HAr), 7.55–7.50
(m, 2H; HAr), 7.48–7.42 (m, 1H; HAr), 0.46 ppm (d, J=0.6 Hz, 9H;
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Me-H8, Me-H9, Me-H10,), 7.79 (dt, J(H,H)=4.6 Hz, J(H,P)=1.4 Hz,
2H; Ar-H4, Ar-H5), 8.70 ppm (m, 2H; Ar-H3, Ar-H6); 13C NMR
(176 MHz, CD2Cl2): d=31.6 (d, 3J(C,P)=8.1 Hz; Me-C8, Me-C9, Me-
1
Me); 13C NMR (101 MHz, CD2Cl2): d=185.7 (d, J(P,C)=74.7 Hz; C=
Chem. Eur. J. 2015, 21, 11096 – 11109
11106
ꢀ 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim