(5S,6S)-4,5-Dimethyl-3-methyl­acryloyl-6-phenyl-1,3,4-oxadiazinan-2-one

Knott, S.A.; Hitchcock, S.R.; Ferrence, G.M.

doi:10.1107/S1600536808013986

organic compounds

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ISSN: 2056-9890

Volume 64| Part 6| June 2008| Page o1101

doi:10.1107/S1600536808013986

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(5S,6S)-4,5-Dimethyl-3-methylacryloyl-6-phenyl-1,3,4-oxadiazinan-2-one

Stanley A. Knott,^a Shawn R. Hitchcock ^a and Gregory M. Ferrence ^a ^*

^aCB 4160, Department of Chemistry, Illinois State University, Normal, IL 61790, USA
^*Correspondence e-mail: ferrence@illinoisstate.edu

(Received 9 May 2008; accepted 9 May 2008; online 17 May 2008)

The title compound, C₁₅H₁₈N₂O₃, is an example of an oxadiazinan-2-one with significant interaction between the N₃-acyl and N₄-methyl groups. These steric interactions result in a large torsion angle between the two carbonyl groups, not present with acyl substituents with less steric demand.

Related literature

For related literature, see: Bruno et al. 2004 ; Burgeson et al. (2004 ); Casper et al. (2002a ,b ); Ferrence et al. (2003 ); Hitchcock et al. (2001 , 2004 ); Szczepura et al. (2004 ); Trepanier et al. (1968 ).

Experimental

Crystal data

C₁₅H₁₈N₂O₃
M_r = 274.31
Orthorhombic, P 2₁ 2₁ 2₁
a = 8.7962 (6) Å
b = 9.7797 (6) Å
c = 16.6782 (11) Å
V = 1434.73 (16) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 193 (2) K
0.46 × 0.38 × 0.21 mm

Data collection

Bruker P4/R4/SMART 1000 CCD diffractometer
Absorption correction: multi-scan (SADABS in SAINT-Plus; Bruker, 2003 ) T_min = 0.865, T_max = 0.982
9610 measured reflections
1702 independent reflections
1593 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.080
S = 1.07
1702 reflections
181 parameters
H-atom parameters constrained
Δρ_max = 0.15 e Å⁻³
Δρ_min = −0.13 e Å⁻³

Data collection: SMART (Bruker, 2003); cell refinement: SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus; program(s) used to solve structure: SIR2004 (Burla et al., 2005 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ) and publCIF (Westrip, 2008 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808013986/zl2116sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808013986/zl2116Isup2.hkl

checkCIF report

Comment top

In recent years, the synthesis of varying oxadiazinanones has led to chiral auxiliaries used in aldol addition reactions. The fundamental heterocyclic structure of related 1,3,4-oxadiazinan-2-one compounds has been known for nearly forty years (Trepanier et al., 1968); however, it has not been until recent years that more detailed conformational studies have been performed on species containing an N₃-acyl substituent (Hitchcock et al., 2001; Casper et al., 2002a). The influence of the N₃-acyl substituent is of significant importance in these studies. When the N₃-acyl substituent is of low steric demand the two carbonyls found in the molecule are co-planar and point at one another. However, when the N₃-substituent is of high steric demand, repulsive steric interactions between the N₃-acyl substituent and the N₄-methyl group cause the two carbonyls to twist out of planarity. The molecule represented herein is an example of a structure in which the acyl substituent at the N₃ position has a high steric demand.

Herein we report the single-crystal X-ray structure of a vinyl-acylated pseudoephedrine-derived 1,3,4-oxadiazinan-2-one (I). Several structures for various N₃ substituted oxadiazananones have been published (Burgeson et al., 2004; Casper et al., 2002b; Ferrence et al., 2003; Hitchcock et al., 2001, 2004). Also, a compound unsubstituted at the N₃ position has been synthesized (Szczepura et al., 2004). A Mogul (Bruno et al. 2004) geometry check showed all non-H bond angles, distances and torsions to be within typical ranges. The structures of previously reported acetyl, propionyl, and t-butylacetyl substituents at the N₃ position exhibit syn-parallel carbonyls. In contrast, in the title compound the 150.8 (2)° O16—C15—N3—C2 and 132.4 (3)° O20—C2—C15—O16 torsion angles are indicative of anti-parallel arrangement of the imide carbonyl groups. It appears likely that this arrangement helps to relieve steric congestion between the O16 carbonyl and the vinyl moiety while at the same time avoiding steric interactions between the N₄ methyl group and the vinyl CH₂ group. The O16—C15—C17—C18 torsion angle is 130.5 (2)°. The potential for steric interactions is further illustrated in the Jmol enhanced figure (Fig. 2).

Related literature top

For related literature, see: Bruno et al. 2004; Burgeson et al. (2004); Casper et al. (2002a,b); Ferrence et al. (2003); Hitchcock et al. (2001, 2004); Szczepura et al. (2004); Trepanier et al. (1968).

Experimental top

The title compound was prepared by acylation of pseudoephedrine derived 1,3,4-oxadiazinan-2-one using sodium hexamethyldisilazane and methylacrylolyl chloride (Casper et al., 2002a).

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SMART (Bruker, 2003); data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999) and publCIF (Westrip, 2008).

Figures top

	Fig. 1. The molecular structure of compound (I), with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. J mol enhanced figure of I. The default view shows the asymmetric unit which is the main residue depicted with a space-filling perspective. Several Jmol button scripts are provided to highlight key structural and crystallographic features.

(5S,6S)-4,5-Dimethyl-3-methylacryloyl-6-phenyl- 1,3,4-oxadiazinan-2-one top

Crystal data top

C₁₅H₁₈N₂O₃	F(000) = 584
M_r = 274.31	D_x = 1.27 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 7730 reflections
a = 8.7962 (6) Å	θ = 3.3–26.4°
b = 9.7797 (6) Å	µ = 0.09 mm⁻¹
c = 16.6782 (11) Å	T = 193 K
V = 1434.73 (16) Å³	Prism, colourless
Z = 4	0.46 × 0.38 × 0.21 mm

Data collection top

Bruker P4/R4/SMART 1000 CCD diffractometer	1702 independent reflections
Radiation source: sealed tube	1593 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
/w scans	θ_max = 26.4°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS in SAINT-Plus; Bruker, 2003)	h = −10→11
T_min = 0.865, T_max = 0.982	k = −11→12
9610 measured reflections	l = −20→20

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.032	w = 1/[σ²(F_o²) + (0.039P)² + 0.2942P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.080	(Δ/σ)_max < 0.001
S = 1.07	Δρ_max = 0.15 e Å⁻³
1702 reflections	Δρ_min = −0.13 e Å⁻³
181 parameters

Crystal data top

C₁₅H₁₈N₂O₃	V = 1434.73 (16) Å³
M_r = 274.31	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 8.7962 (6) Å	µ = 0.09 mm⁻¹
b = 9.7797 (6) Å	T = 193 K
c = 16.6782 (11) Å	0.46 × 0.38 × 0.21 mm

Data collection top

Bruker P4/R4/SMART 1000 CCD diffractometer	1702 independent reflections
Absorption correction: multi-scan (SADABS in SAINT-Plus; Bruker, 2003)	1593 reflections with I > 2σ(I)
T_min = 0.865, T_max = 0.982	R_int = 0.032
9610 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	0 restraints
wR(F²) = 0.080	H-atom parameters constrained
S = 1.07	Δρ_max = 0.15 e Å⁻³
1702 reflections	Δρ_min = −0.13 e Å⁻³
181 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
O1	0.56811 (14)	0.91142 (13)	0.46559 (7)	0.0296 (3)
C2	0.6459 (2)	0.85642 (18)	0.40478 (10)	0.0255 (4)
N3	0.56076 (17)	0.80251 (16)	0.34127 (8)	0.0270 (3)
N4	0.40508 (18)	0.76608 (16)	0.35333 (9)	0.0281 (3)
C5	0.3312 (2)	0.8846 (2)	0.39098 (11)	0.0275 (4)
H5	0.3518	0.9668	0.357	0.033*
C6	0.4005 (2)	0.90915 (19)	0.47323 (10)	0.0266 (4)
H6	0.3726	0.8301	0.5083	0.032*
C7	0.3531 (2)	1.0377 (2)	0.51526 (11)	0.0293 (4)
C8	0.2870 (2)	1.0285 (2)	0.59025 (12)	0.0382 (5)
H8	0.2767	0.9415	0.615	0.046*
C9	0.2356 (3)	1.1443 (3)	0.63006 (14)	0.0501 (6)
H9	0.1901	1.1364	0.6815	0.06*
C10	0.2509 (3)	1.2699 (3)	0.59454 (16)	0.0548 (7)
H10	0.2146	1.3495	0.6211	0.066*
C11	0.3186 (3)	1.2809 (3)	0.52055 (17)	0.0581 (7)
H11	0.3305	1.3685	0.4967	0.07*
C12	0.3698 (3)	1.1662 (2)	0.48046 (14)	0.0432 (5)
H12	0.4163	1.1749	0.4293	0.052*
C13	0.1593 (2)	0.8641 (2)	0.39546 (12)	0.0368 (5)
H13A	0.119	0.8483	0.3415	0.055*
H13B	0.1119	0.9459	0.4184	0.055*
H13C	0.1366	0.7849	0.4294	0.055*
C14	0.3987 (2)	0.63742 (19)	0.39932 (11)	0.0345 (4)
H14A	0.4509	0.5651	0.3694	0.052*
H14B	0.2923	0.6114	0.4078	0.052*
H14C	0.4486	0.6503	0.4513	0.052*
C15	0.6276 (2)	0.7502 (2)	0.27061 (11)	0.0302 (4)
O16	0.56288 (17)	0.66036 (17)	0.23419 (8)	0.0436 (4)
C17	0.7710 (2)	0.8135 (3)	0.24081 (11)	0.0395 (5)
C18	0.7866 (3)	0.9514 (3)	0.23698 (14)	0.0552 (7)
H18A	0.8742	0.9903	0.2127	0.066*
H18B	0.7099	1.009	0.2586	0.066*
C19	0.8816 (3)	0.7179 (3)	0.20957 (19)	0.0697 (9)
H19A	0.8464	0.6242	0.2191	0.105*	0.5
H19B	0.9793	0.7319	0.2366	0.105*	0.5
H19C	0.8941	0.7327	0.1518	0.105*	0.5
H19D	0.9668	0.7684	0.1859	0.105*	0.5
H19E	0.8339	0.6606	0.1684	0.105*	0.5
H19F	0.9191	0.6599	0.2532	0.105*	0.5
O20	0.78185 (15)	0.85606 (15)	0.40662 (8)	0.0334 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0264 (7)	0.0361 (7)	0.0264 (6)	0.0026 (6)	−0.0026 (5)	−0.0042 (5)
C2	0.0276 (9)	0.0240 (9)	0.0249 (8)	0.0016 (7)	−0.0016 (7)	0.0032 (7)
N3	0.0232 (8)	0.0327 (8)	0.0250 (7)	−0.0007 (7)	0.0007 (6)	−0.0016 (6)
N4	0.0239 (8)	0.0330 (8)	0.0273 (7)	−0.0043 (7)	0.0012 (6)	−0.0013 (6)
C5	0.0253 (9)	0.0304 (10)	0.0267 (8)	−0.0014 (8)	0.0024 (7)	0.0034 (7)
C6	0.0255 (9)	0.0277 (9)	0.0266 (8)	−0.0010 (8)	0.0024 (8)	0.0026 (7)
C7	0.0252 (9)	0.0312 (10)	0.0315 (9)	−0.0004 (8)	−0.0011 (8)	−0.0018 (8)
C8	0.0376 (11)	0.0409 (12)	0.0360 (10)	−0.0041 (10)	0.0027 (9)	−0.0055 (9)
C9	0.0417 (12)	0.0642 (16)	0.0445 (11)	0.0043 (12)	0.0035 (10)	−0.0207 (12)
C10	0.0533 (15)	0.0482 (14)	0.0628 (15)	0.0179 (12)	−0.0107 (13)	−0.0232 (12)
C11	0.0741 (18)	0.0294 (12)	0.0707 (17)	0.0106 (12)	−0.0103 (15)	−0.0008 (12)
C12	0.0514 (13)	0.0342 (11)	0.0442 (11)	0.0028 (10)	0.0044 (10)	0.0044 (10)
C13	0.0248 (9)	0.0471 (12)	0.0384 (10)	−0.0031 (9)	0.0016 (8)	0.0015 (10)
C14	0.0386 (10)	0.0299 (10)	0.0349 (9)	−0.0052 (9)	0.0028 (9)	−0.0033 (8)
C15	0.0278 (10)	0.0379 (11)	0.0249 (8)	0.0029 (8)	−0.0018 (7)	−0.0026 (8)
O16	0.0390 (8)	0.0533 (9)	0.0385 (7)	−0.0053 (8)	0.0051 (6)	−0.0169 (7)
C17	0.0302 (10)	0.0612 (14)	0.0272 (9)	−0.0053 (10)	0.0019 (8)	−0.0060 (9)
C18	0.0665 (17)	0.0539 (15)	0.0453 (12)	−0.0102 (14)	0.0131 (12)	0.0109 (11)
C19	0.0401 (14)	0.089 (2)	0.0800 (18)	−0.0012 (15)	0.0159 (14)	−0.0317 (17)
O20	0.0253 (7)	0.0426 (8)	0.0324 (6)	0.0028 (6)	−0.0047 (5)	−0.0008 (6)

Geometric parameters (Å, º) top

O1—C2	1.336 (2)	C11—C12	1.382 (3)
O1—C6	1.480 (2)	C11—H11	0.95
C2—O20	1.196 (2)	C12—H12	0.95
C2—N3	1.400 (2)	C13—H13A	0.98
N3—C15	1.413 (2)	C13—H13B	0.98
N3—N4	1.429 (2)	C13—H13C	0.98
N4—C5	1.470 (2)	C14—H14A	0.98
N4—C14	1.475 (2)	C14—H14B	0.98
C5—C6	1.520 (2)	C14—H14C	0.98
C5—C13	1.528 (3)	C15—O16	1.210 (2)
C5—H5	1	C15—C17	1.491 (3)
C6—C7	1.499 (3)	C17—C18	1.357 (4)
C6—H6	1	C17—C19	1.447 (3)
C7—C8	1.382 (3)	C18—H18A	0.95
C7—C12	1.392 (3)	C18—H18B	0.95
C8—C9	1.388 (3)	C19—H19A	0.98
C8—H8	0.95	C19—H19B	0.98
C9—C10	1.371 (4)	C19—H19C	0.98
C9—H9	0.95	C19—H19D	0.98
C10—C11	1.375 (4)	C19—H19E	0.98
C10—H10	0.95	C19—H19F	0.98

C2—O1—C6	124.71 (14)	C5—C13—H13B	109.5
O20—C2—O1	119.58 (17)	H13A—C13—H13B	109.5
O20—C2—N3	123.57 (17)	C5—C13—H13C	109.5
O1—C2—N3	116.85 (15)	H13A—C13—H13C	109.5
C2—N3—C15	123.02 (15)	H13B—C13—H13C	109.5
C2—N3—N4	119.99 (14)	N4—C14—H14A	109.5
C15—N3—N4	115.19 (14)	N4—C14—H14B	109.5
N3—N4—C5	106.68 (14)	H14A—C14—H14B	109.5
N3—N4—C14	108.80 (14)	N4—C14—H14C	109.5
C5—N4—C14	115.71 (14)	H14A—C14—H14C	109.5
N4—C5—C6	109.45 (14)	H14B—C14—H14C	109.5
N4—C5—C13	110.80 (16)	O16—C15—N3	119.08 (18)
C6—C5—C13	111.93 (15)	O16—C15—C17	122.15 (18)
N4—C5—H5	108.2	N3—C15—C17	118.67 (17)
C6—C5—H5	108.2	C18—C17—C19	123.9 (3)
C13—C5—H5	108.2	C18—C17—C15	120.9 (2)
O1—C6—C7	107.77 (14)	C19—C17—C15	114.9 (2)
O1—C6—C5	108.91 (14)	C17—C18—H18A	120
C7—C6—C5	116.28 (15)	C17—C18—H18B	120
O1—C6—H6	107.9	H18A—C18—H18B	120
C7—C6—H6	107.9	C17—C19—H19A	109.5
C5—C6—H6	107.9	C17—C19—H19B	109.5
C8—C7—C12	118.74 (19)	H19A—C19—H19B	109.5
C8—C7—C6	119.06 (18)	C17—C19—H19C	109.5
C12—C7—C6	122.18 (17)	H19A—C19—H19C	109.5
C7—C8—C9	121.1 (2)	H19B—C19—H19C	109.5
C7—C8—H8	119.4	C17—C19—H19D	109.5
C9—C8—H8	119.4	H19A—C19—H19D	141.1
C10—C9—C8	119.5 (2)	H19B—C19—H19D	56.3
C10—C9—H9	120.3	H19C—C19—H19D	56.3
C8—C9—H9	120.3	C17—C19—H19E	109.5
C9—C10—C11	120.0 (2)	H19A—C19—H19E	56.3
C9—C10—H10	120	H19B—C19—H19E	141.1
C11—C10—H10	120	H19C—C19—H19E	56.3
C10—C11—C12	120.8 (2)	H19D—C19—H19E	109.5
C10—C11—H11	119.6	C17—C19—H19F	109.5
C12—C11—H11	119.6	H19A—C19—H19F	56.3
C11—C12—C7	119.8 (2)	H19B—C19—H19F	56.3
C11—C12—H12	120.1	H19C—C19—H19F	141.1
C7—C12—H12	120.1	H19D—C19—H19F	109.5
C5—C13—H13A	109.5	H19E—C19—H19F	109.5

C6—O1—C2—O20	−175.30 (16)	C5—C6—C7—C8	122.65 (19)
C6—O1—C2—N3	5.1 (3)	O1—C6—C7—C12	66.8 (2)
O20—C2—N3—C15	−4.2 (3)	C5—C6—C7—C12	−55.7 (2)
O1—C2—N3—C15	175.31 (16)	C12—C7—C8—C9	1.1 (3)
O20—C2—N3—N4	159.76 (17)	C6—C7—C8—C9	−177.33 (19)
O1—C2—N3—N4	−20.7 (2)	C7—C8—C9—C10	−0.2 (3)
C2—N3—N4—C5	50.5 (2)	C8—C9—C10—C11	−0.9 (4)
C15—N3—N4—C5	−144.27 (15)	C9—C10—C11—C12	1.1 (4)
C2—N3—N4—C14	−74.94 (19)	C10—C11—C12—C7	−0.2 (4)
C15—N3—N4—C14	90.25 (17)	C8—C7—C12—C11	−0.9 (3)
N3—N4—C5—C6	−64.27 (17)	C6—C7—C12—C11	177.5 (2)
C14—N4—C5—C6	56.91 (19)	C2—N3—C15—O16	150.77 (18)
N3—N4—C5—C13	171.82 (15)	N4—N3—C15—O16	−13.9 (3)
C14—N4—C5—C13	−67.0 (2)	C2—N3—C15—C17	−32.8 (3)
C2—O1—C6—C7	−147.65 (16)	N4—N3—C15—C17	162.50 (16)
C2—O1—C6—C5	−20.7 (2)	O16—C15—C17—C18	130.5 (2)
N4—C5—C6—O1	50.02 (18)	N3—C15—C17—C18	−45.8 (3)
C13—C5—C6—O1	173.25 (16)	O16—C15—C17—C19	−43.4 (3)
N4—C5—C6—C7	171.95 (15)	N3—C15—C17—C19	140.3 (2)
C13—C5—C6—C7	−64.8 (2)	O20—C2—C15—O16	132.4 (3)
O1—C6—C7—C8	−114.81 (19)

Experimental details

Crystal data
Chemical formula	C₁₅H₁₈N₂O₃
M_r	274.31
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	193
a, b, c (Å)	8.7962 (6), 9.7797 (6), 16.6782 (11)
V (Å³)	1434.73 (16)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.46 × 0.38 × 0.21

Data collection
Diffractometer	Bruker P4/R4/SMART 1000 CCD diffractometer
Absorption correction	Multi-scan (SADABS in SAINT-Plus; Bruker, 2003)
T_min, T_max	0.865, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	9610, 1702, 1593
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.080, 1.07
No. of reflections	1702
No. of parameters	181
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.15, −0.13

Computer programs: SMART (Bruker, 2003), SAINT-Plus (Bruker, 2003), SIR2004 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999) and publCIF (Westrip, 2008).

Acknowledgements

This material is based upon work supported by the US National Science Foundation (CHE-0348158) (to GMF) and the American Chemical Society Petroleum Research Fund (to SRH & GMF). GMF thanks Robert McDonald and Michael Ferguson, X-ray Crystallography Laboratory, Department of Chemistry, University of Alberta for the data collection.

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