6-Ethoxy-1,2,3,4-tetra­hydro-2,2,4-tri­methyl­quinoline

As part of structural studies of 6-ethoxy-2,3,4-tetra­hydro-2,2,4-tri­methyl­quinoline derivatives, the crystal structure of the title compound, C₁₄H₂₁NO, has been investigated. The conformation of the tetra­hydro­pyridine ring differs markedly from that of similar compounds.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.053
• wR factor = 0.142
• Data-to-parameter ratio = 17.8

checkCIF/PLATON results

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Alert level C
PLAT420_ALERT_2_C D-H Without Acceptor       N1     -   H1     ...          ?

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 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
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: CAD-4 EXPRESS (Enraf Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

6-ethoxy-1,2,3,4-tetrahydro-2,2,4-trimethylquinoline

Crystal data

C14H21NO	F(000) = 480
Mr = 219.32	Dx = 1.099 Mg m^−3
Monoclinic, P21/c	Melting point = 311–312 K
Hall symbol: -P 2ybc	Cu Kα radiation, λ = 1.5418 Å
a = 13.196 (4) Å	Cell parameters from 25 reflections
b = 8.865 (6) Å	θ = 30–35°
c = 11.330 (11) Å	µ = 0.53 mm^−1
β = 90.77 (6)°	T = 293 K
V = 1325.3 (16) Å^3	Prism, colourless
Z = 4	0.3 × 0.3 × 0.3 mm

Data collection

Enraf-Nonius CAD-4 diffractometer	Rint = 0.058
Radiation source: Fine-focus sealed tube	θmax = 74.9°, θmin = 3.4°
Graphite monochromator	h = −16→16
Non–profiled ω/2θ scans	k = −11→11
5533 measured reflections	l = 0→14
2717 independent reflections	1 standard reflections every 60 min
1805 reflections with I > 2σ(I)	intensity decay: 3%

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)] = 0.053	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.143	H atoms treated by a mixture of independent and constrained refinement
S = 0.99	w = 1/[σ^2(Fo^2) + (0.0647P)^2] where P = (Fo^2 + 2Fc^2)/3
2717 reflections	(Δ/σ)max < 0.001
153 parameters	Δρmax = 0.21 e Å^−3
0 restraints	Δρmin = −0.12 e Å^−3

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

	x	y	z	Uiso*/Ueq
N1	0.38148 (12)	0.02040 (16)	0.17518 (12)	0.0640 (4)
H1	0.4348 (16)	0.063 (3)	0.1840 (18)	0.105 (8)*
C2	0.35815 (13)	−0.10006 (17)	0.25961 (13)	0.0619 (4)
C21	0.40091 (14)	−0.2521 (2)	0.21842 (19)	0.0782 (5)
H21A	0.3734	−0.2762	0.1418	0.117*
H21B	0.3827	−0.3295	0.2735	0.117*
H21C	0.4734	−0.2457	0.2142	0.117*
C22	0.40617 (18)	−0.0575 (3)	0.37778 (16)	0.0960 (7)
H22A	0.4779	−0.0447	0.3686	0.144*
H22B	0.3939	−0.1361	0.4341	0.144*
H22C	0.3771	0.0351	0.4052	0.144*
C3	0.24376 (13)	−0.1064 (2)	0.26736 (14)	0.0693 (4)
H3A	0.2195	−0.0098	0.2958	0.083*
H3B	0.2256	−0.1823	0.3250	0.083*
C4	0.18988 (12)	−0.1424 (2)	0.15114 (14)	0.0686 (5)
H4	0.2033	−0.2487	0.1334	0.082*
C41	0.07622 (16)	−0.1249 (4)	0.1615 (2)	0.1203 (10)
H41A	0.0603	−0.0216	0.1785	0.180*
H41B	0.0523	−0.1880	0.2241	0.180*
H41C	0.0440	−0.1541	0.0885	0.180*
C5	0.23523 (11)	−0.04933 (16)	0.05200 (12)	0.0544 (3)
C6	0.18569 (11)	−0.03689 (16)	−0.05646 (13)	0.0577 (4)
H6	0.1240	−0.0860	−0.0675	0.069*
C7	0.22513 (11)	0.04636 (17)	−0.14911 (12)	0.0571 (4)
O7	0.16833 (9)	0.04510 (14)	−0.25191 (9)	0.0731 (4)
C71	0.20138 (15)	0.1343 (2)	−0.34731 (14)	0.0798 (5)
H71A	0.2673	0.1001	−0.3732	0.096*
H71B	0.2073	0.2389	−0.3230	0.096*
C72	0.12574 (18)	0.1203 (3)	−0.44545 (16)	0.1035 (8)
H72A	0.1213	0.0168	−0.4700	0.155*
H72B	0.1465	0.1814	−0.5108	0.155*
H72C	0.0607	0.1535	−0.4189	0.155*
C8	0.31598 (12)	0.12003 (17)	−0.13336 (13)	0.0602 (4)
H8	0.3427	0.1779	−0.1939	0.072*
C9	0.36729 (12)	0.10722 (17)	−0.02630 (13)	0.0593 (4)
H9	0.4292	0.1561	−0.0164	0.071*
C10	0.32872 (11)	0.02296 (15)	0.06727 (12)	0.0521 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0703 (9)	0.0581 (7)	0.0634 (7)	−0.0115 (7)	−0.0095 (7)	0.0061 (6)
C2	0.0685 (10)	0.0568 (8)	0.0601 (8)	−0.0027 (8)	−0.0062 (7)	0.0093 (7)
C21	0.0686 (11)	0.0634 (10)	0.1025 (13)	0.0053 (8)	0.0005 (10)	0.0123 (9)
C22	0.1199 (18)	0.0993 (15)	0.0682 (10)	−0.0184 (13)	−0.0228 (11)	0.0164 (10)
C3	0.0726 (11)	0.0688 (10)	0.0666 (8)	0.0034 (9)	0.0105 (8)	0.0130 (8)
C4	0.0561 (9)	0.0752 (10)	0.0747 (9)	−0.0060 (8)	0.0049 (8)	0.0195 (8)
C41	0.0619 (12)	0.190 (3)	0.1099 (15)	−0.0093 (15)	0.0148 (11)	0.0584 (18)
C5	0.0488 (8)	0.0514 (7)	0.0630 (8)	0.0007 (6)	0.0036 (6)	0.0033 (6)
C6	0.0469 (7)	0.0572 (8)	0.0689 (8)	−0.0033 (7)	−0.0004 (6)	0.0028 (7)
C7	0.0543 (8)	0.0578 (8)	0.0591 (8)	0.0029 (7)	−0.0022 (6)	0.0009 (7)
O7	0.0719 (8)	0.0841 (8)	0.0630 (6)	−0.0124 (6)	−0.0086 (6)	0.0120 (6)
C71	0.0949 (14)	0.0805 (12)	0.0639 (9)	−0.0057 (10)	−0.0053 (9)	0.0151 (8)
C72	0.1145 (18)	0.1261 (19)	0.0696 (11)	−0.0077 (15)	−0.0147 (11)	0.0216 (12)
C8	0.0637 (9)	0.0569 (8)	0.0599 (8)	−0.0051 (7)	0.0035 (7)	0.0060 (7)
C9	0.0569 (9)	0.0557 (8)	0.0654 (8)	−0.0122 (7)	0.0003 (7)	0.0038 (7)
C10	0.0529 (8)	0.0461 (7)	0.0571 (7)	−0.0026 (6)	−0.0004 (6)	0.0015 (6)

Geometric parameters (Å, º)

N1—C10	1.399 (2)	C41—H41B	0.9600
N1—C2	1.469 (2)	C41—H41C	0.9600
N1—H1	0.80 (2)	C5—C6	1.388 (2)
C2—C3	1.514 (2)	C5—C10	1.399 (2)
C2—C22	1.521 (3)	C6—C7	1.390 (2)
C2—C21	1.537 (2)	C6—H6	0.9300
C21—H21A	0.9600	C7—C8	1.375 (2)
C21—H21B	0.9600	C7—O7	1.377 (2)
C21—H21C	0.9600	O7—C71	1.413 (2)
C22—H22A	0.9600	C71—C72	1.489 (3)
C22—H22B	0.9600	C71—H71A	0.9700
C22—H22C	0.9600	C71—H71B	0.9700
C3—C4	1.522 (3)	C72—H72A	0.9600
C3—H3A	0.9700	C72—H72B	0.9600
C3—H3B	0.9700	C72—H72C	0.9600
C4—C41	1.514 (3)	C8—C9	1.386 (2)
C4—C5	1.523 (2)	C8—H8	0.9300
C4—H4	0.9800	C9—C10	1.398 (2)
C41—H41A	0.9600	C9—H9	0.9300
C10—N1—C2	118.34 (14)	H41A—C41—H41B	109.5
C10—N1—H1	121.7 (15)	C4—C41—H41C	109.5
C2—N1—H1	116.8 (16)	H41A—C41—H41C	109.5
N1—C2—C3	106.40 (14)	H41B—C41—H41C	109.5
N1—C2—C22	107.72 (15)	C6—C5—C10	118.49 (14)
C3—C2—C22	111.22 (16)	C6—C5—C4	120.72 (14)
N1—C2—C21	111.04 (15)	C10—C5—C4	120.78 (14)
C3—C2—C21	110.84 (14)	C5—C6—C7	122.27 (14)
C22—C2—C21	109.55 (16)	C5—C6—H6	118.9
C2—C21—H21A	109.5	C7—C6—H6	118.9
C2—C21—H21B	109.5	C8—C7—O7	125.28 (14)
H21A—C21—H21B	109.5	C8—C7—C6	119.27 (14)
C2—C21—H21C	109.5	O7—C7—C6	115.44 (14)
H21A—C21—H21C	109.5	C7—O7—C71	118.20 (14)
H21B—C21—H21C	109.5	O7—C71—C72	108.27 (17)
C2—C22—H22A	109.5	O7—C71—H71A	110.0
C2—C22—H22B	109.5	C72—C71—H71A	110.0
H22A—C22—H22B	109.5	O7—C71—H71B	110.0
C2—C22—H22C	109.5	C72—C71—H71B	110.0
H22A—C22—H22C	109.5	H71A—C71—H71B	108.4
H22B—C22—H22C	109.5	C71—C72—H72A	109.5
C2—C3—C4	114.33 (14)	C71—C72—H72B	109.5
C2—C3—H3A	108.7	H72A—C72—H72B	109.5
C4—C3—H3A	108.7	C71—C72—H72C	109.5
C2—C3—H3B	108.7	H72A—C72—H72C	109.5
C4—C3—H3B	108.7	H72B—C72—H72C	109.5
H3A—C3—H3B	107.6	C7—C8—C9	119.32 (14)
C41—C4—C3	111.30 (17)	C7—C8—H8	120.3
C41—C4—C5	113.67 (15)	C9—C8—H8	120.3
C3—C4—C5	109.93 (14)	C8—C9—C10	121.93 (14)
C41—C4—H4	107.2	C8—C9—H9	119.0
C3—C4—H4	107.2	C10—C9—H9	119.0
C5—C4—H4	107.2	C9—C10—N1	119.30 (14)
C4—C41—H41A	109.5	C9—C10—C5	118.71 (14)
C4—C41—H41B	109.5	N1—C10—C5	121.89 (14)
C10—N1—C2—C3	−47.77 (19)	C5—C6—C7—O7	178.57 (13)
C10—N1—C2—C22	−167.12 (16)	C8—C7—O7—C71	−4.6 (2)
C10—N1—C2—C21	72.9 (2)	C6—C7—O7—C71	176.52 (15)
N1—C2—C3—C4	60.71 (18)	C7—O7—C71—C72	−177.32 (17)
C22—C2—C3—C4	177.74 (16)	O7—C7—C8—C9	−177.56 (15)
C21—C2—C3—C4	−60.12 (18)	C6—C7—C8—C9	1.3 (2)
C2—C3—C4—C41	−171.89 (17)	C7—C8—C9—C10	−0.9 (2)
C2—C3—C4—C5	−45.04 (19)	C8—C9—C10—N1	−176.81 (14)
C41—C4—C5—C6	−40.4 (2)	C8—C9—C10—C5	−0.5 (2)
C3—C4—C5—C6	−165.90 (14)	C2—N1—C10—C9	−162.32 (14)
C41—C4—C5—C10	140.95 (19)	C2—N1—C10—C5	21.5 (2)
C3—C4—C5—C10	15.4 (2)	C6—C5—C10—C9	1.4 (2)
C10—C5—C6—C7	−0.9 (2)	C4—C5—C10—C9	−179.96 (14)
C4—C5—C6—C7	−179.63 (14)	C6—C5—C10—N1	177.59 (14)
C5—C6—C7—C8	−0.4 (2)	C4—C5—C10—N1	−3.7 (2)