cis-(3-Methyl­pentane-2,4-dionato-κ²O,O′)bis­(2-phenyl­pyridine-κ²C,N)iridium(III)

The title compound, [Ir(C₁₁H₈N)₂(C₆H₉O₂)], is a neutral mononuclear Ir^III complex, with the metal centre coordinated by two N atoms and two C atoms from two 2-phenyl­pyridine ligands [mean Ir—N and Ir—C bond lengths 2.044 (5) and 2.001 (6) Å, respectively], and two O atoms from the β-diketonate ligand [mean Ir—O bond length 2.134 (4) Å], forming a distorted octa­hedral environment.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.010 Å
• R factor = 0.036
• wR factor = 0.080
• Data-to-parameter ratio = 17.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT030_ALERT_1_C _diffrn_reflns_number .LE.  _reflns_number_total          ?

Author Response: Omitted 2 reflections because of OFF Center.

PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.58 Ratio

Author Response: I think no problem.

PLAT342_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...         10

Author Response: I think no problem.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

---

Computing details

Data collection: STADI4 (Stoe & Cie, 1996); cell refinement: STADI4; data reduction: X-RED (Stoe & Cie, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

cis-(3-Methylpentane-2,4-dionato-κ²O,O')bis(2-phenylpyridine- κ²C,N)iridium(III)

Crystal data

[Ir(C11H8N)2(C6H9O2)]	F(000) = 1200
Mr = 613.70	Dx = 1.748 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2yn	Cell parameters from 30 reflections
a = 11.589 (2) Å	θ = 9.6–10.4°
b = 9.589 (2) Å	µ = 5.75 mm^−1
c = 20.993 (2) Å	T = 298 K
β = 91.678 (9)°	Tetragonal prism, yellow
V = 2331.9 (7) Å^3	0.50 × 0.20 × 0.13 mm
Z = 4

Data collection

Stoe STADI-4 four-circle diffractometer	4152 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.000
Graphite monochromator	θmax = 27.5°, θmin = 1.9°
ω/2θ scans	h = −15→15
Absorption correction: numerical (X-SHAPE; Stoe & Cie, 1996)	k = 0→12
Tmin = 0.346, Tmax = 0.581	l = 0→27
5327 measured reflections	3 standard reflections every 60 min
5327 independent reflections	intensity decay: 3.5%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.080	H-atom parameters constrained
S = 1.13	w = 1/[σ^2(Fo^2) + (0.0265P)^2 + 4.2427P] where P = (Fo^2 + 2Fc^2)/3
5327 reflections	(Δ/σ)max < 0.001
301 parameters	Δρmax = 1.37 e Å^−3
0 restraints	Δρmin = −0.71 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Ir	0.746468 (19)	0.27995 (2)	0.069284 (10)	0.03230 (7)
O1	0.6006 (3)	0.2090 (4)	0.01494 (18)	0.0388 (9)
O2	0.8469 (3)	0.1748 (5)	−0.00019 (19)	0.0417 (10)
N1	0.7580 (4)	0.4636 (5)	0.0209 (2)	0.0405 (12)
N2	0.7326 (4)	0.1074 (5)	0.1260 (2)	0.0357 (11)
C1	0.6769 (6)	0.5098 (7)	−0.0213 (3)	0.0489 (16)
H1	0.6141	0.4526	−0.0313	0.059*
C2	0.6834 (7)	0.6376 (7)	−0.0501 (3)	0.0571 (19)
H2	0.6254	0.6672	−0.0785	0.069*
C3	0.7773 (8)	0.7216 (8)	−0.0362 (4)	0.070 (2)
H3	0.7841	0.8084	−0.0555	0.083*
C4	0.8615 (7)	0.6750 (8)	0.0069 (4)	0.060 (2)
H4	0.9257	0.7303	0.0162	0.072*
C5	0.8505 (6)	0.5450 (7)	0.0365 (3)	0.0446 (16)
C6	0.9263 (6)	0.4842 (7)	0.0861 (3)	0.0450 (16)
C7	1.0297 (6)	0.5465 (8)	0.1072 (4)	0.061 (2)
H7	1.0517	0.6316	0.0902	0.073*
C8	1.0991 (6)	0.4827 (10)	0.1530 (4)	0.067 (2)
H8	1.1675	0.5248	0.1670	0.081*
C9	1.0664 (6)	0.3556 (10)	0.1780 (3)	0.059 (2)
H9	1.1130	0.3121	0.2089	0.071*
C10	0.9643 (5)	0.2930 (8)	0.1571 (3)	0.0479 (16)
H10	0.9437	0.2073	0.1741	0.058*
C11	0.8914 (5)	0.3556 (7)	0.1109 (3)	0.0382 (14)
C12	0.6427 (5)	0.3589 (7)	0.1345 (3)	0.0383 (14)
C13	0.5984 (6)	0.4924 (7)	0.1394 (3)	0.0508 (17)
H13	0.6244	0.5616	0.1123	0.061*
C14	0.5160 (7)	0.5253 (9)	0.1838 (3)	0.063 (2)
H14	0.4882	0.6161	0.1863	0.076*
C15	0.4748 (7)	0.4236 (10)	0.2244 (3)	0.069 (2)
H15	0.4173	0.4452	0.2528	0.082*
C16	0.5195 (6)	0.2915 (9)	0.2226 (3)	0.0557 (18)
H16	0.4932	0.2234	0.2502	0.067*
C17	0.6046 (5)	0.2593 (7)	0.1792 (3)	0.0414 (15)
C18	0.6584 (5)	0.1209 (7)	0.1761 (3)	0.0359 (13)
C19	0.6465 (6)	0.0110 (8)	0.2180 (3)	0.0496 (17)
H19	0.5987	0.0206	0.2525	0.059*
C20	0.7037 (6)	−0.1109 (8)	0.2094 (3)	0.0549 (19)
H20	0.6951	−0.1841	0.2379	0.066*
C21	0.7756 (6)	−0.1262 (7)	0.1574 (3)	0.0521 (17)
H21	0.8142	−0.2094	0.1501	0.063*
C22	0.7871 (5)	−0.0128 (7)	0.1174 (3)	0.0425 (15)
H22	0.8351	−0.0211	0.0829	0.051*
C23	0.5994 (5)	0.1508 (7)	−0.0392 (3)	0.0387 (13)
C24	0.4787 (6)	0.1243 (8)	−0.0660 (3)	0.0583 (19)
H24A	0.4707	0.0275	−0.0769	0.087*
H24B	0.4657	0.1801	−0.1035	0.087*
H24C	0.4234	0.1485	−0.0348	0.087*
C25	0.6952 (6)	0.1102 (7)	−0.0749 (3)	0.0443 (15)
C26	0.6706 (8)	0.0485 (12)	−0.1411 (4)	0.092 (3)
H26A	0.7389	0.0540	−0.1657	0.138*
H26B	0.6095	0.1001	−0.1621	0.138*
H26C	0.6478	−0.0473	−0.1370	0.138*
C27	0.8091 (6)	0.1208 (6)	−0.0522 (3)	0.0391 (14)
C28	0.9069 (6)	0.0589 (8)	−0.0911 (3)	0.061 (2)
H28A	0.9352	0.1285	−0.1196	0.091*
H28B	0.8781	−0.0193	−0.1154	0.091*
H28C	0.9684	0.0287	−0.0628	0.091*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ir	0.03008 (11)	0.03528 (12)	0.03178 (11)	−0.00597 (11)	0.00481 (7)	−0.00259 (11)
O1	0.034 (2)	0.040 (2)	0.042 (2)	−0.007 (2)	0.0015 (17)	−0.0055 (19)
O2	0.034 (2)	0.047 (3)	0.045 (2)	−0.0066 (19)	0.0087 (18)	−0.008 (2)
N1	0.044 (3)	0.041 (3)	0.037 (3)	−0.007 (2)	0.012 (2)	−0.001 (2)
N2	0.028 (2)	0.041 (3)	0.038 (3)	−0.002 (2)	0.0005 (19)	0.002 (2)
C1	0.053 (4)	0.046 (4)	0.048 (4)	0.001 (3)	0.005 (3)	0.007 (3)
C2	0.072 (5)	0.044 (4)	0.057 (4)	0.003 (4)	0.012 (4)	0.012 (3)
C3	0.099 (7)	0.037 (4)	0.073 (5)	−0.010 (5)	0.023 (5)	0.007 (4)
C4	0.072 (5)	0.043 (4)	0.066 (5)	−0.021 (4)	0.021 (4)	−0.004 (4)
C5	0.045 (4)	0.046 (4)	0.045 (3)	−0.013 (3)	0.021 (3)	−0.012 (3)
C6	0.042 (4)	0.051 (4)	0.043 (3)	−0.014 (3)	0.007 (3)	−0.014 (3)
C7	0.047 (4)	0.056 (5)	0.080 (5)	−0.021 (4)	0.017 (4)	−0.021 (4)
C8	0.036 (4)	0.097 (7)	0.069 (5)	−0.018 (4)	0.005 (4)	−0.027 (5)
C9	0.036 (4)	0.094 (6)	0.048 (4)	0.006 (4)	−0.005 (3)	−0.017 (4)
C10	0.039 (3)	0.065 (5)	0.040 (3)	−0.001 (3)	0.003 (3)	−0.010 (3)
C11	0.032 (3)	0.049 (4)	0.034 (3)	−0.004 (3)	0.005 (2)	−0.011 (3)
C12	0.035 (3)	0.045 (4)	0.035 (3)	−0.006 (3)	0.003 (2)	−0.009 (3)
C13	0.060 (4)	0.046 (4)	0.047 (4)	0.004 (3)	0.017 (3)	−0.003 (3)
C14	0.071 (5)	0.067 (5)	0.052 (4)	0.022 (4)	0.016 (4)	−0.003 (4)
C15	0.064 (5)	0.091 (7)	0.052 (4)	0.014 (5)	0.025 (4)	−0.008 (4)
C16	0.050 (4)	0.073 (5)	0.044 (3)	−0.002 (4)	0.017 (3)	0.000 (4)
C17	0.040 (3)	0.055 (4)	0.029 (3)	−0.010 (3)	0.001 (2)	−0.006 (3)
C18	0.026 (3)	0.045 (4)	0.036 (3)	−0.007 (3)	−0.003 (2)	0.000 (3)
C19	0.053 (4)	0.056 (5)	0.039 (3)	−0.002 (4)	−0.002 (3)	0.010 (3)
C20	0.057 (4)	0.060 (5)	0.048 (4)	−0.011 (4)	−0.004 (3)	0.019 (3)
C21	0.046 (4)	0.047 (4)	0.063 (4)	0.005 (3)	−0.009 (3)	0.015 (3)
C22	0.029 (3)	0.053 (4)	0.046 (3)	0.000 (3)	0.001 (3)	0.005 (3)
C23	0.042 (3)	0.035 (3)	0.039 (3)	−0.010 (3)	−0.003 (3)	0.002 (3)
C24	0.047 (4)	0.070 (5)	0.058 (4)	−0.006 (4)	−0.011 (3)	−0.004 (4)
C25	0.049 (4)	0.049 (4)	0.035 (3)	−0.007 (3)	0.004 (3)	−0.002 (3)
C26	0.079 (6)	0.137 (9)	0.060 (5)	0.006 (6)	−0.007 (5)	−0.037 (6)
C27	0.046 (4)	0.034 (3)	0.038 (3)	−0.005 (3)	0.006 (3)	0.000 (3)
C28	0.053 (4)	0.071 (5)	0.060 (4)	−0.011 (4)	0.022 (4)	−0.022 (4)

Geometric parameters (Å, º)

Ir—C12	1.997 (6)	C12—C17	1.418 (8)
Ir—C11	2.005 (6)	C13—C14	1.390 (9)
Ir—N1	2.039 (5)	C13—H13	0.9300
Ir—N2	2.048 (5)	C14—C15	1.389 (11)
Ir—O1	2.123 (4)	C14—H14	0.9300
Ir—O2	2.144 (4)	C15—C16	1.370 (11)
O1—C23	1.266 (7)	C15—H15	0.9300
O2—C27	1.275 (7)	C16—C17	1.398 (8)
N1—C1	1.348 (8)	C16—H16	0.9300
N1—C5	1.358 (8)	C17—C18	1.469 (9)
N2—C22	1.329 (8)	C18—C19	1.382 (8)
N2—C18	1.383 (7)	C19—C20	1.358 (10)
C1—C2	1.369 (9)	C19—H19	0.9300
C1—H1	0.9300	C20—C21	1.399 (10)
C2—C3	1.378 (11)	C20—H20	0.9300
C2—H2	0.9300	C21—C22	1.383 (9)
C3—C4	1.385 (11)	C21—H21	0.9300
C3—H3	0.9300	C22—H22	0.9300
C4—C5	1.400 (10)	C23—C25	1.414 (9)
C4—H4	0.9300	C23—C24	1.513 (8)
C5—C6	1.464 (9)	C24—H24A	0.9600
C6—C7	1.398 (9)	C24—H24B	0.9600
C6—C11	1.403 (9)	C24—H24C	0.9600
C7—C8	1.378 (11)	C25—C27	1.393 (9)
C7—H7	0.9300	C25—C26	1.529 (9)
C8—C9	1.384 (12)	C26—H26A	0.9600
C8—H8	0.9300	C26—H26B	0.9600
C9—C10	1.386 (9)	C26—H26C	0.9600
C9—H9	0.9300	C27—C28	1.536 (9)
C10—C11	1.402 (9)	C28—H28A	0.9600
C10—H10	0.9300	C28—H28B	0.9600
C12—C13	1.384 (9)	C28—H28C	0.9600
C12—Ir—C11	94.5 (2)	C12—C13—H13	119.2
C12—Ir—N1	93.6 (2)	C14—C13—H13	119.2
C11—Ir—N1	80.7 (2)	C15—C14—C13	120.5 (7)
C12—Ir—N2	81.3 (2)	C15—C14—H14	119.8
C11—Ir—N2	96.8 (2)	C13—C14—H14	119.8
N1—Ir—N2	174.2 (2)	C16—C15—C14	119.7 (7)
C12—Ir—O1	90.2 (2)	C16—C15—H15	120.2
C11—Ir—O1	173.2 (2)	C14—C15—H15	120.2
N1—Ir—O1	94.1 (2)	C15—C16—C17	119.8 (7)
N2—Ir—O1	88.8 (2)	C15—C16—H16	120.1
C12—Ir—O2	173.8 (2)	C17—C16—H16	120.1
C11—Ir—O2	90.1 (2)	C16—C17—C12	121.5 (7)
N1—Ir—O2	91.3 (2)	C16—C17—C18	122.5 (6)
N2—Ir—O2	94.0 (2)	C12—C17—C18	116.0 (5)
O1—Ir—O2	85.6 (2)	C19—C18—N2	119.2 (6)
C23—O1—Ir	127.7 (4)	C19—C18—C17	127.6 (6)
C27—O2—Ir	126.4 (4)	N2—C18—C17	113.1 (5)
C1—N1—C5	120.0 (6)	C20—C19—C18	120.9 (6)
C1—N1—Ir	123.8 (4)	C20—C19—H19	119.6
C5—N1—Ir	116.0 (4)	C18—C19—H19	119.6
C22—N2—C18	119.5 (5)	C19—C20—C21	119.9 (6)
C22—N2—Ir	125.2 (4)	C19—C20—H20	120.1
C18—N2—Ir	115.3 (4)	C21—C20—H20	120.1
N1—C1—C2	122.5 (7)	C22—C21—C20	117.5 (7)
N1—C1—H1	118.7	C22—C21—H21	121.3
C2—C1—H1	118.7	C20—C21—H21	121.3
C1—C2—C3	118.9 (8)	N2—C22—C21	123.0 (6)
C1—C2—H2	120.5	N2—C22—H22	118.5
C3—C2—H2	120.5	C21—C22—H22	118.5
C2—C3—C4	119.1 (7)	O1—C23—C25	127.5 (5)
C2—C3—H3	120.5	O1—C23—C24	113.3 (6)
C4—C3—H3	120.5	C25—C23—C24	119.2 (6)
C3—C4—C5	120.4 (7)	C23—C24—H24A	109.5
C3—C4—H4	119.8	C23—C24—H24B	109.5
C5—C4—H4	119.8	H24A—C24—H24B	109.5
N1—C5—C4	119.1 (7)	C23—C24—H24C	109.5
N1—C5—C6	113.3 (6)	H24A—C24—H24C	109.5
C4—C5—C6	127.6 (6)	H24B—C24—H24C	109.5
C7—C6—C11	120.8 (7)	C27—C25—C23	123.3 (6)
C7—C6—C5	123.1 (7)	C27—C25—C26	119.3 (6)
C11—C6—C5	116.1 (5)	C23—C25—C26	117.4 (6)
C8—C7—C6	120.6 (7)	C25—C26—H26A	109.5
C8—C7—H7	119.7	C25—C26—H26B	109.5
C6—C7—H7	119.7	H26A—C26—H26B	109.5
C7—C8—C9	119.6 (7)	C25—C26—H26C	109.5
C7—C8—H8	120.2	H26A—C26—H26C	109.5
C9—C8—H8	120.2	H26B—C26—H26C	109.5
C8—C9—C10	120.1 (7)	O2—C27—C25	128.4 (6)
C8—C9—H9	120.0	O2—C27—C28	111.9 (6)
C10—C9—H9	120.0	C25—C27—C28	119.7 (6)
C9—C10—C11	121.7 (7)	C27—C28—H28A	109.5
C9—C10—H10	119.1	C27—C28—H28B	109.5
C11—C10—H10	119.1	H28A—C28—H28B	109.5
C10—C11—C6	117.2 (6)	C27—C28—H28C	109.5
C13—C12—C17	116.8 (6)	H28A—C28—H28C	109.5
C12—C13—C14	121.6 (7)	H28B—C28—H28C	109.5
C12—Ir—O1—C23	175.6 (5)	N2—Ir—C11—C10	8.4 (6)
N1—Ir—O1—C23	81.9 (5)	O2—Ir—C11—C10	−85.6 (5)
N2—Ir—O1—C23	−103.1 (5)	C12—Ir—C11—C6	−94.7 (5)
O2—Ir—O1—C23	−9.1 (5)	N1—Ir—C11—C6	−1.7 (4)
C11—Ir—O2—C27	−166.2 (5)	N2—Ir—C11—C6	−176.4 (4)
N1—Ir—O2—C27	−85.5 (5)	O2—Ir—C11—C6	89.5 (4)
N2—Ir—O2—C27	97.0 (5)	C11—Ir—C12—C13	82.0 (6)
O1—Ir—O2—C27	8.5 (5)	N1—Ir—C12—C13	1.0 (6)
C12—Ir—N1—C1	−80.9 (5)	N2—Ir—C12—C13	178.1 (6)
C11—Ir—N1—C1	−174.8 (5)	O1—Ir—C12—C13	−93.1 (6)
O1—Ir—N1—C1	9.6 (5)	C11—Ir—C12—C17	−102.5 (4)
O2—Ir—N1—C1	95.3 (5)	N1—Ir—C12—C17	176.6 (4)
C12—Ir—N1—C5	94.8 (4)	N2—Ir—C12—C17	−6.3 (4)
C11—Ir—N1—C5	0.9 (4)	O1—Ir—C12—C17	82.4 (4)
O1—Ir—N1—C5	−174.7 (4)	C17—C12—C13—C14	−3.2 (10)
O2—Ir—N1—C5	−89.0 (4)	Ir—C12—C13—C14	172.2 (5)
C12—Ir—N2—C22	−177.1 (5)	C12—C13—C14—C15	−0.6 (12)
C11—Ir—N2—C22	−83.6 (5)	C13—C14—C15—C16	2.8 (12)
O1—Ir—N2—C22	92.4 (5)	C14—C15—C16—C17	−1.1 (12)
O2—Ir—N2—C22	6.9 (5)	C15—C16—C17—C12	−2.9 (10)
C12—Ir—N2—C18	4.0 (4)	C15—C16—C17—C18	178.1 (6)
C11—Ir—N2—C18	97.5 (4)	C13—C12—C17—C16	5.0 (9)
O1—Ir—N2—C18	−86.5 (4)	Ir—C12—C17—C16	−171.1 (5)
O2—Ir—N2—C18	−172.0 (4)	C13—C12—C17—C18	−176.0 (5)
C5—N1—C1—C2	0.2 (10)	Ir—C12—C17—C18	7.9 (6)
Ir—N1—C1—C2	175.7 (5)	C22—N2—C18—C19	3.0 (8)
N1—C1—C2—C3	1.1 (11)	Ir—N2—C18—C19	−178.0 (4)
C1—C2—C3—C4	−0.7 (11)	C22—N2—C18—C17	−179.8 (5)
C2—C3—C4—C5	−0.8 (12)	Ir—N2—C18—C17	−0.8 (6)
C1—N1—C5—C4	−1.7 (9)	C16—C17—C18—C19	−8.7 (10)
Ir—N1—C5—C4	−177.6 (5)	C12—C17—C18—C19	172.3 (6)
C1—N1—C5—C6	176.0 (5)	C16—C17—C18—N2	174.4 (5)
Ir—N1—C5—C6	0.2 (7)	C12—C17—C18—N2	−4.6 (7)
C3—C4—C5—N1	2.0 (10)	N2—C18—C19—C20	−2.1 (9)
C3—C4—C5—C6	−175.4 (7)	C17—C18—C19—C20	−178.9 (6)
N1—C5—C6—C7	176.6 (6)	C18—C19—C20—C21	−0.1 (10)
C4—C5—C6—C7	−5.9 (10)	C19—C20—C21—C22	1.5 (10)
N1—C5—C6—C11	−1.7 (8)	C18—N2—C22—C21	−1.7 (9)
C4—C5—C6—C11	175.9 (6)	Ir—N2—C22—C21	179.4 (5)
C11—C6—C7—C8	−0.2 (10)	C20—C21—C22—N2	−0.6 (10)
C5—C6—C7—C8	−178.4 (6)	Ir—O1—C23—C25	4.6 (9)
C6—C7—C8—C9	0.3 (11)	Ir—O1—C23—C24	−175.5 (4)
C7—C8—C9—C10	0.0 (11)	O1—C23—C25—C27	4.8 (11)
C8—C9—C10—C11	−0.4 (10)	C24—C23—C25—C27	−175.1 (6)
C9—C10—C11—C6	0.5 (9)	O1—C23—C25—C26	−176.8 (7)
C9—C10—C11—Ir	175.5 (5)	C24—C23—C25—C26	3.4 (10)
C7—C6—C11—C10	−0.2 (9)	Ir—O2—C27—C25	−3.6 (10)
C5—C6—C11—C10	178.1 (5)	Ir—O2—C27—C28	178.0 (4)
C7—C6—C11—Ir	−175.9 (5)	C23—C25—C27—O2	−5.3 (11)
C5—C6—C11—Ir	2.4 (7)	C26—C25—C27—O2	176.3 (7)
C12—Ir—C11—C10	90.2 (6)	C23—C25—C27—C28	173.0 (6)
N1—Ir—C11—C10	−176.9 (6)	C26—C25—C27—C28	−5.4 (10)