Buspirone free base

In the solid state, the title compound, 8-{4-[4-(pyrimidin-2-yl)­piperazin-1-yl]but­yl}-8-aza­spiro­[4.5]decane-7,9-dione, C₂₁H₃₁N₅O₂, exists as an extended conformer with the piperazinyl and glutarimide units having chair and sofa conformations, respectively, while the butyl chain is trans,trans,trans.

Key indicators

• Single-crystal X-ray study
• T = 567 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.046
• wR factor = 0.150
• Data-to-parameter ratio = 17.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT022_ALERT_3_C Ratio Unique / Expected Reflections too Low ....       0.94
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.97

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 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

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Computing details

Data collection: KM-4 Software (Kuma Diffraction, 1999); cell refinement: KM-4 Software; data reduction: KM-4 Software; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC (Sheldrick, 1990); software used to prepare material for publication: SHELXL97 and enCIFer (Allen et al., 2004).

8-[4-(4-pyrimidin-2-ylpiperazin-1-yl)butyl]-8-azaspiro[4,5]decane-7,9-dione

Crystal data

C21H31N5O2	F(000) = 832
Mr = 385.51	Dx = 1.230 Mg m^−3
Monoclinic, P21/c	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybc	Cell parameters from 50 reflections
a = 10.548 (2) Å	θ = 6–22°
b = 11.764 (2) Å	µ = 0.65 mm^−1
c = 16.998 (3) Å	T = 292 K
β = 99.28 (3)°	Prism, colorless
V = 2081.6 (7) Å^3	0.35 × 0.28 × 0.19 mm
Z = 4

Data collection

Kuma KM4 four-circle diffractometer	Rint = 0.046
Radiation source: fine-focus sealed tube	θmax = 81.3°, θmin = 4.3°
Graphite monochromator	h = −13→13
ω–2θ scans	k = 0→15
4454 measured reflections	l = 0→21
4320 independent reflections	3 standard reflections every 100 reflections
2791 reflections with I > 2σ(I)	intensity decay: 0.1%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.046	H-atom parameters constrained
wR(F^2) = 0.150	w = 1/[σ^2(Fo^2) + (0.08P)^2 + 0.26P] where P = (Fo^2 + 2Fc^2)/3
S = 1.06	(Δ/σ)max < 0.001
4320 reflections	Δρmax = 0.20 e Å^−3
254 parameters	Δρmin = −0.15 e Å^−3
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0008 (2)

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	Uiso*/Ueq
N1	0.65633 (17)	0.29318 (15)	0.12095 (10)	0.0634 (4)
C2	0.58135 (17)	0.20416 (15)	0.13173 (10)	0.0484 (4)
C4	0.6373 (2)	0.1043 (2)	0.02871 (12)	0.0642 (5)
H4	0.6306	0.0398	−0.0033	0.077*
N5	0.56743 (16)	0.10915 (14)	0.08718 (9)	0.0558 (4)
C5	0.7181 (2)	0.1888 (2)	0.01329 (13)	0.0702 (6)
H5	0.7664	0.1833	−0.0277	0.084*
C6	0.7239 (2)	0.2822 (2)	0.06166 (13)	0.0712 (6)
H6	0.7781	0.3414	0.0526	0.085*
N2	0.51537 (16)	0.21005 (12)	0.19382 (9)	0.0540 (4)
C11	0.5056 (2)	0.31577 (15)	0.23694 (11)	0.0555 (4)
H11A	0.4272	0.3551	0.2146	0.067*
H11B	0.5777	0.3646	0.2314	0.067*
C12	0.50501 (19)	0.29129 (16)	0.32412 (11)	0.0543 (4)
H12A	0.5866	0.2579	0.3473	0.065*
H12B	0.4949	0.3619	0.3519	0.065*
N3	0.40118 (14)	0.21389 (12)	0.33457 (8)	0.0458 (3)
C13	0.42048 (18)	0.10728 (15)	0.29413 (11)	0.0511 (4)
H13A	0.3532	0.0540	0.3016	0.061*
H13B	0.5023	0.0744	0.3175	0.061*
C14	0.41867 (19)	0.12625 (15)	0.20606 (11)	0.0547 (4)
H14A	0.4358	0.0551	0.1809	0.066*
H14B	0.3344	0.1527	0.1816	0.066*
C15	0.39634 (18)	0.19628 (18)	0.41919 (10)	0.0547 (4)
H15A	0.4045	0.2693	0.4460	0.066*
H15B	0.4692	0.1501	0.4421	0.066*
C16	0.27429 (18)	0.13927 (19)	0.43495 (11)	0.0567 (5)
H16A	0.2706	0.0628	0.4134	0.068*
H16B	0.2008	0.1809	0.4076	0.068*
C17	0.26603 (19)	0.1336 (2)	0.52312 (11)	0.0617 (5)
H17A	0.3325	0.0833	0.5495	0.074*
H17B	0.2811	0.2087	0.5464	0.074*
C18	0.13605 (19)	0.09098 (19)	0.53696 (11)	0.0579 (5)
H18A	0.0700	0.1430	0.5122	0.069*
H18B	0.1197	0.0173	0.5117	0.069*
N4	0.12816 (15)	0.08068 (13)	0.62232 (9)	0.0503 (4)
C19	0.09726 (18)	0.17800 (15)	0.66237 (12)	0.0526 (4)
O1	0.07278 (19)	0.26518 (13)	0.62565 (10)	0.0817 (5)
C20	0.10124 (18)	0.17056 (16)	0.75032 (11)	0.0516 (4)
H20A	0.0399	0.2243	0.7656	0.062*
H20B	0.1860	0.1933	0.7765	0.062*
C21	0.07164 (16)	0.05300 (15)	0.78065 (10)	0.0466 (4)
C22	0.15831 (19)	−0.03164 (17)	0.74689 (12)	0.0588 (5)
H22A	0.2460	−0.0196	0.7731	0.071*
H22B	0.1336	−0.1079	0.7601	0.071*
C23	0.15520 (19)	−0.02485 (16)	0.65882 (12)	0.0567 (5)
O2	0.1778 (2)	−0.10608 (14)	0.61948 (11)	0.0919 (6)
C24	−0.1339 (2)	0.0819 (2)	0.82513 (15)	0.0759 (6)
H24A	−0.1745	0.1531	0.8065	0.091*
H24B	−0.1987	0.0321	0.8409	0.091*
C25	−0.07245 (17)	0.02654 (17)	0.75916 (12)	0.0558 (4)
H25A	−0.1074	0.0584	0.7076	0.067*
H25B	−0.0872	−0.0549	0.7577	0.067*
C26	−0.0284 (2)	0.1028 (3)	0.89458 (14)	0.0813 (7)
H26A	−0.0492	0.0675	0.9425	0.098*
H26B	−0.0164	0.1836	0.9041	0.098*
C27	0.0918 (2)	0.0502 (2)	0.87194 (11)	0.0634 (5)
H27A	0.1024	−0.0273	0.8913	0.076*
H27B	0.1672	0.0937	0.8941	0.076*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0681 (10)	0.0685 (11)	0.0587 (10)	−0.0125 (8)	0.0253 (8)	0.0010 (8)
C2	0.0508 (9)	0.0517 (9)	0.0435 (9)	0.0029 (7)	0.0098 (7)	0.0033 (7)
C4	0.0677 (12)	0.0766 (14)	0.0500 (11)	0.0200 (11)	0.0146 (9)	−0.0029 (9)
N5	0.0629 (9)	0.0579 (9)	0.0481 (8)	0.0060 (7)	0.0138 (7)	−0.0042 (7)
C5	0.0588 (11)	0.1003 (17)	0.0561 (12)	0.0171 (11)	0.0236 (9)	0.0062 (12)
C6	0.0644 (12)	0.0893 (16)	0.0654 (13)	−0.0045 (11)	0.0273 (10)	0.0087 (12)
N2	0.0692 (10)	0.0452 (8)	0.0531 (9)	−0.0118 (7)	0.0260 (7)	−0.0075 (6)
C11	0.0754 (12)	0.0410 (8)	0.0554 (11)	−0.0108 (8)	0.0261 (9)	−0.0040 (8)
C12	0.0639 (11)	0.0497 (9)	0.0523 (10)	−0.0145 (8)	0.0181 (8)	−0.0055 (8)
N3	0.0513 (7)	0.0449 (7)	0.0435 (7)	−0.0048 (6)	0.0147 (6)	−0.0022 (6)
C13	0.0613 (10)	0.0409 (8)	0.0546 (10)	−0.0066 (7)	0.0199 (8)	−0.0005 (7)
C14	0.0678 (11)	0.0463 (9)	0.0539 (10)	−0.0122 (8)	0.0215 (8)	−0.0089 (8)
C15	0.0544 (10)	0.0670 (12)	0.0437 (9)	−0.0134 (8)	0.0114 (7)	−0.0012 (8)
C16	0.0563 (10)	0.0713 (12)	0.0437 (9)	−0.0144 (9)	0.0114 (8)	0.0006 (8)
C17	0.0591 (11)	0.0833 (14)	0.0448 (10)	−0.0191 (10)	0.0147 (8)	−0.0026 (9)
C18	0.0583 (10)	0.0714 (12)	0.0462 (10)	−0.0154 (9)	0.0150 (8)	−0.0021 (9)
N4	0.0554 (8)	0.0506 (8)	0.0485 (8)	−0.0048 (6)	0.0190 (6)	−0.0001 (6)
C19	0.0576 (10)	0.0437 (9)	0.0588 (10)	−0.0048 (8)	0.0166 (8)	0.0028 (8)
O1	0.1209 (15)	0.0539 (8)	0.0740 (10)	0.0085 (9)	0.0263 (9)	0.0150 (7)
C20	0.0548 (9)	0.0471 (9)	0.0554 (10)	−0.0061 (8)	0.0167 (8)	−0.0046 (8)
C21	0.0460 (8)	0.0479 (9)	0.0474 (9)	0.0022 (7)	0.0119 (7)	0.0045 (7)
C22	0.0621 (11)	0.0545 (10)	0.0629 (11)	0.0115 (9)	0.0197 (9)	0.0092 (9)
C23	0.0608 (11)	0.0508 (10)	0.0625 (11)	0.0034 (8)	0.0223 (9)	−0.0035 (9)
O2	0.1321 (16)	0.0641 (10)	0.0876 (12)	0.0207 (10)	0.0421 (11)	−0.0119 (8)
C24	0.0530 (11)	0.0857 (16)	0.0945 (17)	−0.0058 (11)	0.0282 (11)	−0.0138 (13)
C25	0.0514 (10)	0.0537 (10)	0.0636 (11)	−0.0069 (8)	0.0128 (8)	0.0028 (8)
C26	0.0741 (14)	0.114 (2)	0.0604 (13)	0.0151 (14)	0.0245 (11)	−0.0004 (13)
C27	0.0611 (11)	0.0812 (14)	0.0491 (10)	0.0086 (10)	0.0124 (8)	0.0083 (9)

Geometric parameters (Å, º)

N1—C6	1.331 (3)	C17—C18	1.514 (3)
N1—C2	1.343 (2)	C17—H17A	0.9700
C2—N5	1.345 (2)	C17—H17B	0.9700
C2—N2	1.356 (2)	C18—N4	1.472 (2)
C4—N5	1.330 (2)	C18—H18A	0.9700
C4—C5	1.362 (3)	C18—H18B	0.9700
C4—H4	0.9300	N4—C23	1.397 (2)
C5—C6	1.368 (3)	N4—C19	1.397 (2)
C5—H5	0.9300	C19—O1	1.207 (2)
C6—H6	0.9300	C19—C20	1.491 (3)
N2—C11	1.456 (2)	C20—C21	1.526 (2)
N2—C14	1.457 (2)	C20—H20A	0.9700
C11—C12	1.511 (2)	C20—H20B	0.9700
C11—H11A	0.9700	C21—C22	1.525 (2)
C11—H11B	0.9700	C21—C27	1.532 (2)
C12—N3	1.457 (2)	C21—C25	1.537 (2)
C12—H12A	0.9700	C22—C23	1.494 (3)
C12—H12B	0.9700	C22—H22A	0.9700
N3—C13	1.460 (2)	C22—H22B	0.9700
N3—C15	1.462 (2)	C23—O2	1.212 (2)
C13—C14	1.511 (3)	C24—C26	1.506 (3)
C13—H13A	0.9700	C24—C25	1.529 (3)
C13—H13B	0.9700	C24—H24A	0.9700
C14—H14A	0.9700	C24—H24B	0.9700
C14—H14B	0.9700	C25—H25A	0.9700
C15—C16	1.513 (2)	C25—H25B	0.9700
C15—H15A	0.9700	C26—C27	1.515 (3)
C15—H15B	0.9700	C26—H26A	0.9700
C16—C17	1.517 (2)	C26—H26B	0.9700
C16—H16A	0.9700	C27—H27A	0.9700
C16—H16B	0.9700	C27—H27B	0.9700
C6—N1—C2	115.25 (19)	C16—C17—H17B	109.3
N1—C2—N5	125.77 (16)	H17A—C17—H17B	108.0
N1—C2—N2	116.99 (16)	N4—C18—C17	112.16 (16)
N5—C2—N2	117.22 (16)	N4—C18—H18A	109.2
N5—C4—C5	123.5 (2)	C17—C18—H18A	109.2
N5—C4—H4	118.3	N4—C18—H18B	109.2
C5—C4—H4	118.3	C17—C18—H18B	109.2
C4—N5—C2	115.67 (18)	H18A—C18—H18B	107.9
C4—C5—C6	116.06 (19)	C23—N4—C19	123.98 (15)
C4—C5—H5	122.0	C23—N4—C18	118.12 (15)
C6—C5—H5	122.0	C19—N4—C18	117.88 (16)
N1—C6—C5	123.8 (2)	O1—C19—N4	119.46 (18)
N1—C6—H6	118.1	O1—C19—C20	122.51 (18)
C5—C6—H6	118.1	N4—C19—C20	117.99 (16)
C2—N2—C11	121.48 (14)	C19—C20—C21	114.69 (15)
C2—N2—C14	122.36 (15)	C19—C20—H20A	108.6
C11—N2—C14	113.46 (14)	C21—C20—H20A	108.6
N2—C11—C12	110.05 (15)	C19—C20—H20B	108.6
N2—C11—H11A	109.6	C21—C20—H20B	108.6
C12—C11—H11A	109.6	H20A—C20—H20B	107.6
N2—C11—H11B	109.6	C22—C21—C20	107.28 (14)
C12—C11—H11B	109.6	C22—C21—C27	111.92 (15)
H11A—C11—H11B	108.2	C20—C21—C27	111.05 (16)
N3—C12—C11	111.15 (15)	C22—C21—C25	114.10 (16)
N3—C12—H12A	109.4	C20—C21—C25	110.60 (15)
C11—C12—H12A	109.4	C27—C21—C25	101.92 (14)
N3—C12—H12B	109.4	C23—C22—C21	115.11 (16)
C11—C12—H12B	109.4	C23—C22—H22A	108.5
H12A—C12—H12B	108.0	C21—C22—H22A	108.5
C12—N3—C13	108.35 (13)	C23—C22—H22B	108.5
C12—N3—C15	110.77 (14)	C21—C22—H22B	108.5
C13—N3—C15	111.77 (14)	H22A—C22—H22B	107.5
N3—C13—C14	111.05 (14)	O2—C23—N4	120.00 (19)
N3—C13—H13A	109.4	O2—C23—C22	122.42 (19)
C14—C13—H13A	109.4	N4—C23—C22	117.55 (16)
N3—C13—H13B	109.4	C26—C24—C25	107.30 (18)
C14—C13—H13B	109.4	C26—C24—H24A	110.3
H13A—C13—H13B	108.0	C25—C24—H24A	110.3
N2—C14—C13	110.13 (15)	C26—C24—H24B	110.3
N2—C14—H14A	109.6	C25—C24—H24B	110.3
C13—C14—H14A	109.6	H24A—C24—H24B	108.5
N2—C14—H14B	109.6	C24—C25—C21	105.05 (16)
C13—C14—H14B	109.6	C24—C25—H25A	110.7
H14A—C14—H14B	108.1	C21—C25—H25A	110.7
N3—C15—C16	113.74 (15)	C24—C25—H25B	110.7
N3—C15—H15A	108.8	C21—C25—H25B	110.7
C16—C15—H15A	108.8	H25A—C25—H25B	108.8
N3—C15—H15B	108.8	C24—C26—C27	106.09 (19)
C16—C15—H15B	108.8	C24—C26—H26A	110.5
H15A—C15—H15B	107.7	C27—C26—H26A	110.5
C15—C16—C17	112.36 (15)	C24—C26—H26B	110.5
C15—C16—H16A	109.1	C27—C26—H26B	110.5
C17—C16—H16A	109.1	H26A—C26—H26B	108.7
C15—C16—H16B	109.1	C26—C27—C21	105.27 (16)
C17—C16—H16B	109.1	C26—C27—H27A	110.7
H16A—C16—H16B	107.9	C21—C27—H27A	110.7
C18—C17—C16	111.47 (16)	C26—C27—H27B	110.7
C18—C17—H17A	109.3	C21—C27—H27B	110.7
C16—C17—H17A	109.3	H27A—C27—H27B	108.8
C18—C17—H17B	109.3
C6—N1—C2—N5	−1.8 (3)	C17—C18—N4—C19	84.1 (2)
C6—N1—C2—N2	177.16 (19)	C23—N4—C19—O1	−178.55 (19)
C5—C4—N5—C2	−0.2 (3)	C18—N4—C19—O1	3.2 (3)
N1—C2—N5—C4	1.5 (3)	C23—N4—C19—C20	3.9 (3)
N2—C2—N5—C4	−177.50 (17)	C18—N4—C19—C20	−174.36 (15)
N5—C4—C5—C6	−0.5 (3)	O1—C19—C20—C21	152.9 (2)
C2—N1—C6—C5	1.0 (3)	N4—C19—C20—C21	−29.6 (2)
C4—C5—C6—N1	0.1 (3)	C19—C20—C21—C22	51.4 (2)
N1—C2—N2—C11	11.9 (3)	C19—C20—C21—C27	174.00 (15)
N5—C2—N2—C11	−169.08 (17)	C19—C20—C21—C25	−73.6 (2)
N1—C2—N2—C14	172.05 (18)	C20—C21—C22—C23	−51.3 (2)
N5—C2—N2—C14	−8.9 (3)	C27—C21—C22—C23	−173.37 (17)
C2—N2—C11—C12	−145.26 (18)	C25—C21—C22—C23	71.5 (2)
C14—N2—C11—C12	52.9 (2)	C19—N4—C23—O2	178.0 (2)
N2—C11—C12—N3	−56.7 (2)	C18—N4—C23—O2	−3.8 (3)
C11—C12—N3—C13	60.6 (2)	C19—N4—C23—C22	−3.6 (3)
C11—C12—N3—C15	−176.46 (16)	C18—N4—C23—C22	174.67 (16)
C12—N3—C13—C14	−60.48 (19)	C21—C22—C23—O2	−152.5 (2)
C15—N3—C13—C14	177.19 (14)	C21—C22—C23—N4	29.1 (3)
C2—N2—C14—C13	145.45 (18)	C26—C24—C25—C21	−18.6 (3)
C11—N2—C14—C13	−52.9 (2)	C22—C21—C25—C24	155.03 (17)
N3—C13—C14—N2	56.5 (2)	C20—C21—C25—C24	−83.9 (2)
C12—N3—C15—C16	166.84 (17)	C27—C21—C25—C24	34.2 (2)
C13—N3—C15—C16	−72.2 (2)	C25—C24—C26—C27	−4.9 (3)
N3—C15—C16—C17	−173.9 (2)	C24—C26—C27—C21	26.8 (3)
C15—C16—C17—C18	172.3 (2)	C22—C21—C27—C26	−159.96 (19)
C16—C17—C18—N4	177.7 (2)	C20—C21—C27—C26	80.2 (2)
C17—C18—N4—C23	−94.3 (2)	C25—C21—C27—C26	−37.6 (2)