R. Roesler et al.
solution, resulting in the formation of a precipitate of triethylamine·hy-
drochloride. The precipitate was filtered off and the volatiles were re-
moved from the filtrate under high vacuum, allowing for the isolation of
the title product as a yellow solid (420 mg, 54%). 1H NMR (400 MHz,
[D8]THF): d=1.41 (s, 9H; tBu), 7.22–7.18 (m, 4H; m-C6F2H3), 7.59–7.54
(m, 2H; p-C6F2H3), 9.38 ppm (s, 1H; N2CH); 19F NMR (376 MHz,
[D8]THF): d=À120.09 ppm (t, 3JFH =7.5 Hz; o-C6F2H3); 13C{1H} NMR
[Rh
to a THF solution (0.5 mL) of (NHC-F0)H (1a) (25 mg, 0.066 mmol) and
the mixture was agitated. Solid [{RhCl(cod)}2] (16 mg, 0.033 mmol) was
ACHTUGTNRENG(NU cod)ACHTUGNTRENN(UGN NHC-F0)] (3a·H2O): KHMDS (13 mg, 0.066 mmol) was added
AHCTUNGTRENNUNG
added to the reaction mixture immediately. Upon mixing, the title prod-
uct deposited out of solution as an orange crystalline solid. The superna-
tant solvent was decanted off and the crystals were dried under high
vacuum (24 mg, 60%). ESI-MS analysis suggests that this solid is free of
coordinated water; however, upon dissolving the sample in [D6]DMSO
for NMR spectroscopic analysis, one equivalent of water can be seen in
(101 MHz, [D8]THF): d=30.7 (s; C
ACHTUNTGRENGU(N CH3)3), 35.4 (s; CACHTUGNTRNE(NUGN CH3)3), 101.4 (s;
2
C-tBu), 113.0 (dd, 2JCF =20.3, 4JCF =3.0 Hz; m-C6F2H3), 115.4 (t, JCF
=
16.8 Hz; i-C6F2H3), 133.1 (t, 3JCF =10.1 Hz; p-C6F2H3), 153.5 (s; CO),
156.6 (s; N2CH), 159.6 ppm (dd, 1JCF =253.2 Hz; o-C6F2H3); IR (KBr
pellet): n˜ =1679.6 cmÀ1 (vs; CO); elemental analysis calcd (%) for
C20H16N2O2F4: C 61.22, H 4.11, N 7.14; found: C 60.87, H 4.21, N 6.97;
MS (EI): m/z: 392.35 [M]+.
the H NMR spectrum of the complex. H NMR (400 MHz, [D6]DMSO):
d=1.28 (s, 9H; tBu), 1.44–1.35 (m, 8H; CH2COD), 1.98 (brs, 6H;
C6H3Me2), 2.37 (brs, 6H; C6H3Me2), 3.09 (brs, 2H; CHCOD), 3.29 (s, 2H;
H2O), 4.01 (brs, 2H; CHCOD), 7.07–7.08 (m, 4H; m-C6H3Me2), 7.16–
7.19 ppm (m, 2H; p-C6H3Me2); 13C{H} NMR (101 MHz, [D6]DMSO): d=
1
1
18.9 (brs; p-C6H
G
3ACHTUNGNERT(UNGN CH3)2), 26.9 (s; CH2COD),
ACHTUNGTRENNUNG
30.7 (s; C(CH3)3), 33.2 (s; CACHTGNUTRENNUNG
G
(CH3)3), 66.5 (d, 1JCRh =15.0 Hz; CHCOD),
a
92.2 (d, 1JCRh =7.3 Hz; CHCOD), 96.1 (s; C-tBu), 126.4 (brs; C6H3), 126.4
(s; C6H3), 127.7 (brs; C6H3), 135.9 (brs; C6H3), 138.5 (brs; C6H3), 142.3
(s; C6H3), 160.1 (s; CO), 206.2 ppm (d, 1JCRh =47.9 Hz; N2C-Rh); IR
(KBr pellet): n˜ =1579.5 cmÀ1 (vs; CO); MS (ESI): m/z: 587.7
[MÀH2O+H]+.
(768 mg, 3.90 mmol) in THF (25 mL). The mixture was stirred for 1 h,
after which time, triethylamine (0.81 mL, 5.84 mmol) was added to the
solution, resulting in the formation of a precipitate of triethylamine·hy-
drochloride. The precipitate was filtered off and the volatiles were re-
moved from the filtrate under high vacuum, yielding a solid. Recrystalli-
zation of the crude solid from THF allowed for the isolation of the title
product as yellow block crystals (1.013 g, 81%). 1H NMR (400 MHz,
[Rh
added to
0.076 mmol) and the mixture was agitated. Solid [{RhClACHTUNGTRENNUNG
A
U
a
[D8]THF): d=1.39 (s, 9H; tBu), 7.24–7.20 (m, 4H; m-C6F3H2), 9.36 ppm
(s, 1H; N2CH); 19F NMR (376 MHz, [D8]THF): d=À116.44 (t, 2F, JFF
=
0.039 mmol) was immediately added to the reaction mixture. Upon
mixing, 3b deposited immediately as an orange solid. The supernatant
solvent was decanted and the crystals were dried under high vacuum.
1H NMR (400 MHz, [D6]DMSO): d=1.24 (s, 9H; tBu), 1.59–1.39 (m,
8H; CH2COD), 3.27 (brs, 2H; CHCOD), 3.31 (s, 2H; H2O), 4.16 (brs, 2H;
4
7.5 Hz; o-C6F3H2), À104.59 ppm (tt, 1F, 3JFH =8.8, 4JFF =7.1 Hz; p-
C6F3H2); 13C{1H} NMR (101 MHz, CD2Cl2): d=30.3 (s; C
ACTHUNGTRNEUNG(CH3)3), 35.0 (s;
CACHTUNGTRENNUNG
(CH3)3), 102.0 (s; C-tBu), 102.0 (td, 2JCF =25.8, 4JCF =4.0 Hz; m-
C6F3H2), 110.9 (td, 2JCF =16.6, 4JCF =5.2 Hz; i-C6F3H2), 151.1 (s; CO),
156.2 (s; N2CH), 159.2 (dm, 1JCF =256.5, 3JCF =5.6 Hz; o-C6F3H2),
164.1 ppm (dt, 1JCF =256.5, 3JCF =14.6 Hz; p-C6F3H2); IR (KBr pellet):
n˜ =1683.4 cmÀ1 (vs; CO); elemental analysis calcd (%) for C20H16N2O2F4:
C 56.08, H 3.29, N 6.54; found: C 56.50, H 3.72, N 6.14; MS (EI): m/z:
428.33 [M]+.
CHCOD), 7.13 (dd, 2H, 3JHF =8.5, 3JHH =8.5 Hz; m-C6F2H3), 7.21 (dd, 2H,
3JHF =9.0, 3JHH =9.0 Hz; m-C6F2H3), 7.51 ppm (tt, 2H, 3JHH =8.3, JHF
=
4
6.2 Hz; p-C6F2H3); 19F NMR (376 MHz, [D6]DMSO): d=À115.52 (m,
2F; o-C6F2H3), À107.26 ppm (m, 2F; o-C6F2H3); 13C{1H} NMR
(101 MHz, [D6]DMSO): d=27.1 (s; CH2COD), 30.7 (s; CACHTNUGTRENUNG(CH3)3), 31.9 (s;
CH2COD), 33.1 (s; CACTHNUTRGNEUNG
(CH3)3), 66.9 (dd, 1JCRh =11.5, JCF =9.0 Hz; CHCOD),
ACHTUNGTRENNUNG
94.6 (s; C-tBu), 95.5 (d, 1JCRh =7.1 Hz; CHCOD), 110.5 (dd, 2JCF =19.2,
4JCF =2.0 Hz; m-C6F2H3), 112.1 (dd, 2JCF =8.1, 4JCF =2.0 Hz; m-C6F2H3),
a
(583 mg, 2.96 mmol) in THF (20 mL). The mixture was stirred for 1 h,
after which time, triethylamine was added to the solution, resulting in the
formation of a precipitate of triethylamine·hydrochloride. The precipitate
was filtered off and the volatiles were removed from the filtrate under
high vacuum, allowing for the isolation of the title product as a yellow
solid (980 mg, 89%). 1H NMR (400 MHz, [D8]THF): d=1.39 (s, 9H;
tBu); 9.61 ppm (s, 1H; N2CH); 19F NMR (376 MHz, CD2Cl2): d=
À160.34 (tm, 4F, 2JFF =20.7 Hz; m-C6F5), À149.08 (t, 2F, 2JFF =20.7 Hz;
p-C6F5), À144.34 ppm (dm, 4F, 2JFF =18.8 Hz; o-C6F5); 13C{1H} NMR
2
120.3 (t, JCF =16.7 Hz; i-C6F2H3), 129.2 (t, JCF =9.6 Hz; p-C6F2H3), 158.0
3
1
(dd, 1JCF =27.3, JCF =5.1 Hz; o-C6F2H3), 159.2 (s; CO), 160.52 (dd, JCF
=
3
35.4, JCF =5.1 Hz; o-C6F2H3), 211.8 ppm (d, JCRh =48.5 Hz; N2C-Rh); IR
(KBr pellet): n˜ =1596.6 cmÀ1 (vs; CO); elemental analysis calcd (%) for
C28H29N2O3F4Rh·C4H8O: C 55.50, H 5.39, N 4.04; found: C 56.45, H 5.23,
N 4.57; MS (EI): m/z: 601.86 [MÀH2O]+.
[Rh
added to
0.070 mmol) and the mixture was agitated. Solid [{RhClACHTUNGTRENNUNG
A
U
a
(101 MHz, CD2Cl2): d=30.0 (s; C
G
(CH3)3), 102.7 (s; C-
tBu), 111.6 (tm, 2JCF =15.2 Hz; i-C6F5), 138.6 (dm, 1JCF =260.6 Hz; m-
0.035 mmol) was added to the reaction mixture immediately. Upon
mixing, the title product deposited out of solution as an orange solid. The
supernatant solvent was decanted and the crystals were dried under high
vacuum. X-ray quality crystals were obtained by slow evaporation of the
solvent from a solution of 3c in THF. 1H NMR (400 MHz, [D6]DMSO):
d=1.24 (s, 9H; tBu), 1.84–1.40 (m, 8H; CH2COD), 3.24 (brs, 2H; CHCOD),
3.28 (s, 2H; H2O), 4.27 (brs, 2H; CHCOD), 7.21 (ddm, 2H, 3JHF =9.1,
C6F5), 143.6 (dtm, 1JCF =260.6, 2JCF =13.1 Hz; p-C6F5), 144.4 (dm, JCF
=
1
255.5 Hz; o-C6F5), 151.6 (s; CO), 155.4 ppm (s; N2CH); IR (KBr pellet):
n˜ =1681.3 cmÀ1 (vs; CO); elemental analysis calcd (%) for C20H16N2O2F4:
C 48.01, H 2.01, N 5.60; found: C 48.02, H 2.06, N 5.08; MS (EI): m/z:
502.39 [M]+.
ACHTUNGTRENNUNG(NHC-F4)K (2b): KHMDS (13 mg, 0.065 mmol) was added to a THF so-
3JHF =9.1 Hz; m-C6F3H2), 7.32 ppm (ddm, 2H, JHF =9.5, JHF =9.5 Hz; m-
C6F3H2); 19F NMR (376 MHz, [D6]DMSO): d=À112.41 (m, 2F; o-
C6F3H2), À109.56 (m, 2F; p-C6F3H2), À103.51 ppm (m, 2F; o-C6F3H2);
13C{1H} NMR (101 MHz, [D6]DMSO): d=27.2 (s; CH2COD), 30.6 (s; C-
3
3
lution (0.5 mL) of (NHC-F4)H (1b) (25 mg, 0.064 mmol) and the mixture
was agitated. Removal of the volatiles in vacuo resulted in the isolation
of the title product as a white powder in quantitative yield. Major spe-
cies: 1H NMR (400 MHz, [D8]THF): d=1.37 (s, 9H; tBu), 6.93–6.89 (m,
4H; m-C6F2H3), 7.21 ppm (m, 2H; p-C6F2H3); 19F NMR (376 MHz,
[D8]THF): d=À120.40 ppm (t, 4F, 3JHF =6.4 Hz; m-C6F2H3);
(CH3)3), 67.1 (dd; 1JCRh =13.9, JCF
ACHNUTTGERGNUN(N CH3)3), 32.0 (s; CH2COD), 33.1 (s; CACHTUNGRTENNUNG =
8.5 Hz; CHCOD), 94.5 (s; C-tBu), 96.1 (d, JCRh =6.1 Hz; CHCOD), 99.4 (td,
2JCF =26.4, 4JCF =2.8 Hz; m-C6F3H2), 100.7 (td, 2JCF =25.6, 4JCF =2.6 Hz;
m-C6F3H2), 117.41 (td, 2JCF =17.2, 4JCF =5.1 Hz; i-C6F3H2), 159.0 (s; CO),
159.2 (ddd, 1JCF =247.6, 3JCF =16.2, 3JCF =8.3 Hz; o-C6F3H2), 159.7 (ddd,
1JCF =256.5, 3JCF =15.9, 3JCF =7.3 Hz; o-C6F3H2), 161.3 (dt, 1JCF =247.5,
3JCF =15.2 Hz; p-C6F3H2), 212.7 ppm (d, 1JCRh =49.4 Hz; N2C-Rh); IR
(KBr pellet): n˜ =1589.7 cmÀ1 (vs; CO); MS (EI): m/z: 637.89 [MÀH2O]+.
13C{H} NMR (101 MHz, [D8]THF): d=31.9 (s; C
ACHTNUGTRNEUNG(CH3)3), 34.6 (s; C-
ACHTUNGTRENNUNG
(CH3)3), 98.9 (s; C-tBu), 111.9 (dd, 2JCF =17.9, 4JCF =6.3 Hz; m-C6F2H3),
2
125.6 (t, JCF =16.1 Hz; i-C6F2H3), 128.0 (t, JCF =9.6 Hz; p-C6F2H3), 160.7
(dd, 1JCF =249.1, 3JCF =5.1 Hz; o-C6F2H3), 161.5 (s; CO), 244.5 ppm (s,
N2C); minor species: 1H NMR (400 MHz, [D8]THF): d=1.33 (9H, s;
tBu), 6.93–6.89 (4H, m; m-C6F2H3), 7.21 ppm (2H, m; p-C6F2H3);
19F NMR (376 MHz, [D8]THF): d=À116.61, À111.50 ppm (4F; m-
[RhACHTUGNNERT(NUNG cod)ACHTUNTGRENNU(NG NHC-F10)] (3d) and [RhAHCUTNRTGENUN(GN cod)ATHCUGNTRENN(UGN NHC-F10)CATHUNTGENRUGN(OH2)] (3d·H2O):
KHMDS (10 mg, 0.050 mmol) was added to a THF solution (0.5 mL) of
C6F2H3); 13C{H} NMR (101 MHz, [D8]THF): d=32.8 (s; C
(CH3)3), 34.4
(s; C
G
(NHC-F10)H (1d) (25 mg, 0.050 mmol) and the mixture was agitated.
14530
ꢀ 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 2010, 16, 14520 – 14533