6,6'-Dimethyl-2,2'-[1,3-diazinane-1,3-diyl-bis(methyl-ene)]diphenol.

In the mol-ecule of the title compound, C(20)H(26)N(2)O(2), the 1,3-diazinane ring adopts a slightly distorted chair conformation and the hy-droxy-benzyl substituents occupy equatorial positions on the N atoms of the heterocyclic ring. There are two intra-molecular O-H⋯N hydrogen bonds between the N atoms of the 1,3-diazinane ring and the hy-droxy groups of the aromatic rings, with an S(6) set-graph motif. However, the two observed intra-molecular hydrogen-bond distances were different. Considering that both N atoms experience the same chemical environment, it is surprising to see the difference in O⋯N distances [2.6771 (14) and 2.8123 (12) Å]. The crystal structure is further stabilized by a C-H⋯π interaction.

Related literature

For a previous determination of a related structure, see: Rivera et al. (2012 ▶). For a related di-Mannich base, see: Rivera et al. (2009 ▶). For the synthesis of the precursor, see: Rivera et al. (2010 ▶). For bond-length data, see: Allen et al. (1987 ▶). For Cremer–Pople puckering parameters, see: Cremer & Pople (1975 ▶). For n class="Chemical">hydrogen-bond graph-set nomenclature, see: Bernstein et al. (1995 ▶). For the background to hydrogen-bond energy in Mannich bases, see: Koll et al. (2006 ▶).

Experimental

Crystal data

C20H26N2O2

M = 326.4

Monoclinic,

a = 31.2788 (5) Å

b = 9.7215 (1) Å

c = 12.4508 (2) Å

β = 107.936 (2)°

V = 3602.00 (10) Å3

Z = 8

Cu Kα radiation

μ = 0.62 mm−1

T = 120 K

0.3 × 0.14 × 0.07 mm

Data collection

Agilent Xcalibur diffractometer with an Atlas (Gemini ultra Cu) detector

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010 ▶) T min = 0.615, T max = 1

20724 measured reflections

3210 independent reflections

2750 reflections with I > 3σ(I)

R int = 0.031

Refinement

R[F 2 > 2σ(F 2)] = 0.034

wR(F 2) = 0.100

S = 1.61

3210 reflections

224 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.15 e Å−3

Δρmin = −0.14 e Å−3

Data collection: CrysAlis PRO (Agilent, 2010 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR2002 (Burla et al., 2003 ▶); program(s) used to refine structure: JANA2006 (Petříček et al., 2006 ▶); molecular graphics: DIAMOND (Brandenburg & Putz, 2005 ▶); software used to prepare material for publication: JANA2006.

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812005284/nk2137sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812005284/nk2137Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812005284/nk2137Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C20H26N2O2	F(000) = 1408
Mr = 326.4	Dx = 1.204 Mg m−3
Monoclinic, C2/c	Cu Kα radiation, λ = 1.5418 Å
Hall symbol: -C 2yc	Cell parameters from 10886 reflections
a = 31.2788 (5) Å	θ = 3.0–67.0°
b = 9.7215 (1) Å	µ = 0.62 mm−1
c = 12.4508 (2) Å	T = 120 K
β = 107.936 (2)°	Prism, colourless
V = 3602.00 (10) Å3	0.3 × 0.14 × 0.07 mm
Z = 8

Agilent Xcalibur diffractometer with an Atlas (Gemini ultra Cu) detector	3210 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source	2750 reflections with I > 3σ(I)
Mirror monochromator	Rint = 0.031
Detector resolution: 10.3784 pixels mm-1	θmax = 67.1°, θmin = 3.0°
Rotation method data acquisition using ω scans	h = −36→37
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010)	k = −11→11
Tmin = 0.615, Tmax = 1	l = −14→13
20724 measured reflections

Refinement on F2	H atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.034	Weighting scheme based on measured s.u.'s w = 1/(σ2(I) + 0.0016I2)
wR(F2) = 0.100	(Δ/σ)max = 0.003
S = 1.61	Δρmax = 0.15 e Å−3
3210 reflections	Δρmin = −0.14 e Å−3
224 parameters	Extinction correction: B–C type 1 Lorentzian isotropic (Becker & Coppens, 1974)
0 restraints	Extinction coefficient: 900 (300)
98 constraints

Experimental. CrysAlis PRO (Agilent Technologies, 2010) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

Refinement. The refinement was carried out against all reflections. The conventional R-factor is always based on F. The goodness of fit as well as the weighted R-factor are based on F and F2 for refinement carried out on F and F2, respectively. The threshold expression is used only for calculating R-factors etc. and it is not relevant to the choice of reflections for refinement.The program used for refinement, Jana2006, uses the weighting scheme based on the experimental expectations, see _refine_ls_weighting_details, that does not force S to be one. Therefore the values of S are usually larger than the ones from the SHELX program.

	x	y	z	Uiso*/Ueq
O1	0.06464 (3)	0.07051 (9)	0.66310 (8)	0.0302 (3)
O2	0.22184 (3)	−0.05521 (9)	0.85547 (8)	0.0307 (3)
N1	0.09336 (3)	−0.12594 (9)	0.55120 (8)	0.0253 (3)
N2	0.17352 (3)	−0.14744 (9)	0.63781 (8)	0.0243 (3)
C1	0.13773 (4)	−0.09468 (12)	0.54144 (10)	0.0246 (4)
C2	0.08708 (4)	−0.27558 (12)	0.55476 (12)	0.0312 (4)
C3	0.12437 (4)	−0.33754 (12)	0.65145 (12)	0.0325 (4)
C4	0.17000 (4)	−0.29827 (12)	0.64228 (11)	0.0287 (4)
C5	0.05832 (4)	−0.06437 (12)	0.45500 (11)	0.0277 (4)
C6	0.05613 (4)	0.08973 (12)	0.46498 (10)	0.0251 (4)
C7	0.05753 (4)	0.14970 (12)	0.56815 (10)	0.0247 (4)
C8	0.05113 (4)	0.29077 (12)	0.57775 (11)	0.0285 (4)
C9	0.04476 (4)	0.37139 (13)	0.48171 (12)	0.0329 (4)
C10	0.04482 (4)	0.31518 (13)	0.37985 (12)	0.0347 (4)
C11	0.05025 (4)	0.17415 (13)	0.37139 (11)	0.0307 (4)
C12	0.05171 (5)	0.35190 (14)	0.68853 (13)	0.0404 (5)
C13	0.21697 (4)	−0.10533 (12)	0.62478 (10)	0.0274 (4)
C14	0.25656 (4)	−0.14837 (11)	0.72318 (10)	0.0244 (4)
C15	0.25775 (4)	−0.11617 (11)	0.83352 (10)	0.0239 (4)
C16	0.29572 (4)	−0.14483 (11)	0.92540 (10)	0.0254 (4)
C17	0.33194 (4)	−0.20947 (11)	0.90430 (11)	0.0272 (4)
C18	0.33074 (4)	−0.24696 (13)	0.79600 (11)	0.0291 (4)
C19	0.29302 (4)	−0.21597 (12)	0.70615 (11)	0.0278 (4)
C20	0.29665 (5)	−0.10650 (14)	1.04259 (11)	0.0353 (5)
H1a	0.140383	−0.134347	0.473167	0.0295*
H1b	0.14095	0.003083	0.536267	0.0295*
H2a	0.087705	−0.315591	0.484768	0.0374*
H2b	0.058548	−0.294608	0.565453	0.0374*
H3a	0.121489	−0.435894	0.64972	0.039*
H3b	0.121758	−0.30502	0.72196	0.039*
H4a	0.193116	−0.33274	0.70673	0.0345*
H4b	0.173643	−0.337606	0.574906	0.0345*
H5a	0.029635	−0.103489	0.45048	0.0332*
H5b	0.064148	−0.087548	0.385863	0.0332*
H9	0.040193	0.468584	0.48637	0.0395*
H10	0.04114	0.37325	0.315261	0.0416*
H11	0.049941	0.134735	0.30046	0.0368*
H12a	0.033234	0.297621	0.721132	0.0605*
H12b	0.081968	0.353116	0.73863	0.0605*
H12c	0.040286	0.44419	0.676862	0.0605*
H13a	0.217355	−0.007301	0.6158	0.0329*
H13b	0.219925	−0.143722	0.556384	0.0329*
H17	0.358424	−0.228617	0.966195	0.0327*
H18	0.355763	−0.293886	0.783351	0.0349*
H19	0.292099	−0.241654	0.631023	0.0334*
H20a	0.272699	−0.152761	1.060976	0.053*
H20b	0.324928	−0.133316	1.095101	0.053*
H20c	0.29292	−0.008831	1.046816	0.053*
H1	0.0756 (5)	−0.0090 (18)	0.6433 (14)	0.0454*
H2	0.1987 (6)	−0.0618 (17)	0.7916 (16)	0.0461*

	U11	U22	U33	U12	U13	U23
O1	0.0322 (5)	0.0307 (5)	0.0310 (5)	−0.0004 (3)	0.0144 (4)	0.0017 (3)
O2	0.0253 (4)	0.0363 (5)	0.0309 (5)	0.0075 (3)	0.0093 (4)	−0.0010 (4)
N1	0.0202 (5)	0.0235 (5)	0.0300 (6)	−0.0009 (4)	0.0046 (4)	0.0006 (4)
N2	0.0197 (5)	0.0255 (5)	0.0262 (5)	0.0013 (3)	0.0051 (4)	0.0026 (4)
C1	0.0215 (6)	0.0258 (6)	0.0251 (6)	0.0006 (4)	0.0051 (5)	0.0010 (4)
C2	0.0264 (6)	0.0243 (6)	0.0404 (7)	−0.0037 (4)	0.0068 (5)	−0.0013 (5)
C3	0.0314 (7)	0.0241 (6)	0.0399 (8)	−0.0020 (5)	0.0080 (5)	0.0042 (5)
C4	0.0288 (6)	0.0253 (6)	0.0298 (7)	0.0035 (4)	0.0057 (5)	0.0017 (5)
C5	0.0206 (6)	0.0274 (6)	0.0314 (7)	−0.0003 (4)	0.0025 (5)	−0.0023 (5)
C6	0.0145 (5)	0.0290 (6)	0.0287 (6)	−0.0006 (4)	0.0022 (4)	−0.0007 (5)
C7	0.0157 (5)	0.0287 (6)	0.0295 (7)	−0.0018 (4)	0.0066 (5)	0.0017 (5)
C8	0.0178 (6)	0.0294 (6)	0.0386 (7)	−0.0017 (4)	0.0089 (5)	−0.0040 (5)
C9	0.0226 (6)	0.0255 (6)	0.0467 (8)	0.0003 (4)	0.0048 (5)	0.0013 (5)
C10	0.0296 (7)	0.0341 (7)	0.0348 (7)	0.0005 (5)	0.0017 (5)	0.0087 (5)
C11	0.0252 (6)	0.0355 (7)	0.0268 (7)	0.0007 (5)	0.0016 (5)	0.0012 (5)
C12	0.0392 (8)	0.0369 (7)	0.0498 (9)	0.0007 (5)	0.0210 (6)	−0.0090 (6)
C13	0.0225 (6)	0.0332 (6)	0.0265 (6)	0.0010 (5)	0.0075 (5)	0.0032 (5)
C14	0.0204 (6)	0.0258 (6)	0.0267 (6)	−0.0002 (4)	0.0068 (5)	0.0021 (4)
C15	0.0221 (6)	0.0217 (5)	0.0291 (6)	0.0008 (4)	0.0097 (5)	0.0010 (4)
C16	0.0251 (6)	0.0226 (6)	0.0278 (6)	−0.0018 (4)	0.0070 (5)	0.0010 (4)
C17	0.0222 (6)	0.0265 (6)	0.0300 (7)	0.0002 (4)	0.0037 (5)	0.0030 (5)
C18	0.0222 (6)	0.0304 (6)	0.0350 (7)	0.0038 (5)	0.0093 (5)	0.0003 (5)
C19	0.0257 (6)	0.0306 (6)	0.0285 (7)	0.0009 (4)	0.0101 (5)	−0.0006 (5)
C20	0.0334 (7)	0.0427 (7)	0.0278 (7)	0.0019 (5)	0.0061 (5)	−0.0009 (5)

O1—C7	1.3704 (15)	C8—C9	1.3918 (19)
O1—H1	0.910 (18)	C8—C12	1.497 (2)
O2—C15	1.3701 (16)	C9—C10	1.382 (2)
O2—H2	0.898 (16)	C9—H9	0.96
N1—C1	1.4619 (16)	C10—C11	1.3895 (18)
N1—C2	1.4703 (15)	C10—H10	0.96
N1—C5	1.4784 (14)	C11—H11	0.96
N2—C1	1.4591 (13)	C12—H12a	0.96
N2—C4	1.4727 (15)	C12—H12b	0.96
N2—C13	1.4753 (16)	C12—H12c	0.96
C1—H1a	0.96	C13—C14	1.5084 (14)
C1—H1b	0.96	C13—H13a	0.96
C2—C3	1.5191 (16)	C13—H13b	0.96
C2—H2a	0.96	C14—C15	1.3983 (18)
C2—H2b	0.96	C14—C19	1.3879 (18)
C3—C4	1.515 (2)	C15—C16	1.4000 (14)
C3—H3a	0.96	C16—C17	1.3894 (18)
C3—H3b	0.96	C16—C20	1.4976 (19)
C4—H4a	0.96	C17—C18	1.3861 (19)
C4—H4b	0.96	C17—H17	0.96
C5—C6	1.5066 (16)	C18—C19	1.3861 (15)
C5—H5a	0.96	C18—H18	0.96
C5—H5b	0.96	C19—H19	0.96
C6—C7	1.3990 (18)	C20—H20a	0.96
C6—C11	1.3903 (18)	C20—H20b	0.96
C7—C8	1.3964 (16)	C20—H20c	0.96
C7—O1—H1	102.6 (11)	C9—C8—C12	121.73 (11)
C15—O2—H2	106.3 (13)	C8—C9—C10	121.71 (12)
C1—N1—C2	110.32 (9)	C8—C9—H9	119.1442
C1—N1—C5	109.53 (10)	C10—C9—H9	119.1447
C2—N1—C5	110.63 (8)	C9—C10—C11	119.64 (13)
C1—N2—C4	109.49 (8)	C9—C10—H10	120.1785
C1—N2—C13	108.15 (9)	C11—C10—H10	120.1783
C4—N2—C13	111.25 (9)	C6—C11—C10	120.44 (13)
N1—C1—N2	111.48 (10)	C6—C11—H11	119.78
N1—C1—H1a	109.4714	C10—C11—H11	119.7804
N1—C1—H1b	109.4721	C8—C12—H12a	109.4711
N2—C1—H1a	109.4702	C8—C12—H12b	109.4722
N2—C1—H1b	109.4711	C8—C12—H12c	109.4711
H1a—C1—H1b	107.3846	H12a—C12—H12b	109.4712
N1—C2—C3	109.82 (9)	H12a—C12—H12c	109.471
N1—C2—H2a	109.471	H12b—C12—H12c	109.4707
N1—C2—H2b	109.4726	N2—C13—C14	112.79 (10)
C3—C2—H2a	109.4711	N2—C13—H13a	109.4717
C3—C2—H2b	109.4718	N2—C13—H13b	109.4711
H2a—C2—H2b	109.1181	C14—C13—H13a	109.4713
C2—C3—C4	110.58 (11)	C14—C13—H13b	109.4711
C2—C3—H3a	109.4709	H13a—C13—H13b	105.9345
C2—C3—H3b	109.4706	C13—C14—C15	120.18 (11)
C4—C3—H3a	109.4712	C13—C14—C19	121.00 (11)
C4—C3—H3b	109.4715	C15—C14—C19	118.79 (10)
H3a—C3—H3b	108.3382	O2—C15—C14	121.16 (9)
N2—C4—C3	109.68 (10)	O2—C15—C16	117.68 (11)
N2—C4—H4a	109.4709	C14—C15—C16	121.16 (11)
N2—C4—H4b	109.4709	C15—C16—C17	118.13 (12)
C3—C4—H4a	109.4718	C15—C16—C20	120.24 (11)
C3—C4—H4b	109.4711	C17—C16—C20	121.63 (10)
H4a—C4—H4b	109.2658	C16—C17—C18	121.56 (10)
N1—C5—C6	112.15 (9)	C16—C17—H17	119.2196
N1—C5—H5a	109.4713	C18—C17—H17	119.2211
N1—C5—H5b	109.4705	C17—C18—C19	119.30 (12)
C6—C5—H5a	109.4715	C17—C18—H18	120.3511
C6—C5—H5b	109.4715	C19—C18—H18	120.3499
H5a—C5—H5b	106.6581	C14—C19—C18	120.99 (12)
C5—C6—C7	120.05 (11)	C14—C19—H19	119.5056
C5—C6—C11	121.03 (11)	C18—C19—H19	119.5079
C7—C6—C11	118.83 (11)	C16—C20—H20a	109.4711
O1—C7—C6	120.60 (10)	C16—C20—H20b	109.4716
O1—C7—C8	117.86 (11)	C16—C20—H20c	109.4707
C6—C7—C8	121.54 (11)	H20a—C20—H20b	109.4715
C7—C8—C9	117.77 (12)	H20a—C20—H20c	109.4703
C7—C8—C12	120.50 (12)	H20b—C20—H20c	109.4722

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.910 (18)	1.818 (19)	2.6771 (14)	156.3 (16)
O2—H2···N2	0.898 (16)	2.013 (18)	2.8123 (12)	147.6 (17)
C17—H17···Cg2i	0.96	2.73	3.5577 (14)	144

Table 1

Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C6–C11 aromatic ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.910 (18)	1.818 (19)	2.6771 (14)	156.3 (16)
O2—H2⋯N2	0.898 (16)	2.013 (18)	2.8123 (12)	147.6 (17)
C17—H17⋯Cg2i	0.96	2.73	3.5577 (14)	144

Symmetry code: (i) .