Table 1.

Log K_p and Related Values for 32 Compounds^a

compound	group	abbr.	melting point (°C)	log $p_{\mathrm{L}}^{\mathrm{o}}$ at 20 °C (atm)	log Kp (av, N = 3)b(m3/μg, 20 °C) (measured)	SD of log Kp (N = 3)b (m3/μg, 20 °C) (measured)	ζ (20 °C)	log $p_{\mathrm{L}}^{\mathrm{o}}$ at 37 °C (atm)a	log [ζ $p_{\mathrm{L}}^{\mathrm{o}}$] at 37 °C	τ20→37	log Kp(m3/μg, 37 °C) (extrapolated)
benzene	1	Ben	5.5	−1.00c	−10.02	0.09	30	−0.67	0.81	0.49	−10.32
toluene	1	Tol	−95	−1.54c	−9.81	0.08	65	−1.17	0.64	0.45	−10.15
isobutyl acetate	1	IsoBAc	−99	−1.71c	−9.76	0.21	84	−1.32	0.60	0.44	−10.12
acetone*	1	Act	−95	−0.61c	−9.75	0.07	6.6	−0.31	0.52	0.52	−10.03
ethylbenzene	1	EtBen	−95	−2.03c	−9.64	0.08	130	−1.62	0.51	0.41	−10.03
p-xylene	1	pXyl	13	−2.07c	−9.63	0.09	150	−1.65	0.51	0.40	−10.03
limonene	1	Lim	−74	−2.85d	−9.59	0.06	780	−2.37	0.53	0.35	−10.04
ethyl butyrate	1	EtBut	−93	−1.76c	−9.50	0.08	53	−1.37	0.35	0.43	−9.87
p-cymene	1	pCym	−68	−2.87c	−9.29	0.11	410	−2.38	0.24	0.34	−9.75
isoamyl acetate	3	IsoAmAc	−78	−2.23c	−9.23	0.10	84	−1.79	0.14	0.38	−9.65
propanal*	2	Pad	−81	−0.47e	−9.15	0.01	1.2	−0.17	−0.09	0.54	−9.43
butyl butyrate	1	BuBut	−92	−2.76f	−8.96	0.04	150	−2.32	−0.14	0.39	−9.37
2,3-pentanedione*	2	AcPr	−52	−1.70g	−8.80	0.02	9.2	−1.27	−0.31	0.40	−9.20
hydroxyacetone*	1	Hact	−17	−2.38h	−8.00	0.26	7.0	−1.97	−1.13	0.41	−8.39
3-methyl-1-butanol	3	MeBuol	−117	−2.58e	−7.91	0.25	8.9	−2.00	−1.05	0.28	−8.46
(+)-aromadendrene	3	Arom	6.8	−4.66i	−7.86	NA	960	−4.20	−1.22	0.37	−8.30
benzaldehyde*	3	Bzad	−26	−2.91c	−7.66	NA	11	−2.45	−1.43	0.37	−8.08
2,3-dimethylpyrazine	3	DiMePy	12	−2.50j	−7.50	0.06	2.9	−1.99	−1.52	0.32	−7.99
(Z)-3-hexen-1-ol	3	Z3H1ol	−61	−3.00k	−7.23	0.09	5.0	−2.56	−1.86	0.38	−7.66
methyl salicylate	3	MeSal	−7.5	−4.16c	−7.11	0.19	53	−3.50	−1.77	0.23	−7.74
2,3,5-trimethylpyrazine	3	TriMePy	<−10	−2.81j	−7.07	NA	2.2	−2.28	−1.94	0.31	−7.58
menthol	3	Men	37	−4.05c	−6.55	0.07	11	−3.46	−2.41	0.27	−7.11
methyl cinnamate	3	MeCinn	36	−4.67c	−6.27	0.02	25	−4.06	−2.66	0.26	−6.86
cinnamaldehyde*	3	Cad	−7.5	−4.64c	−6.14	0.04	17	−4.04	−2.80	0.26	−6.72
benzyl alcohol	3	Bzol	−15	−4.07c	−6.04	0.02	3.8	−3.41	−2.84	0.23	−6.68
2-acetylpyrrole	3	AcPyr	~90	−3.31l	−5.93	0.01	0.50	−2.65	−2.95	0.23	−6.56
methyl anthranilate	3	MeAnth	24	−4.63c	−5.77	0.01	7.3	−4.03	−3.16	0.26	−6.35
nicotine	3	Nic	−79	−4.49m	−5.37 (=Kp,fb)	NA	2.1	−3.89	−3.57	0.27	−5.95 (=Kp,fb)
coumarin	3	Cou	71	−5.64l	−5.17	0.05	19	−4.99	−3.72	0.23	−5.80
ethyl maltol	3	EtMalt	~87	−6.13l	−5.10	0.05	48	−5.43	−3.75	0.21	−5.77
maltol	3	Malt	162	−5.50l	−5.07	0.04	11	−4.80	−3.77	0.21	−5.75
cinnamyl alcohol	3	Cinnol	33	−4.50c	−4.88	0.02	0.70	−3.91	−4.07 av:	0.27 0.34	−5.45

^aFor aldehydes and ketones (marked with *), log K_p values may be too large by ~0.1 due to artifacts caused by polymerization, hemiacetal formation, acetal formation, hemiketal formation, and/or ketal formation in the PG/GL liquid phase; log K_p (m³/μg) values were measured at 20 °C in 50/50 (by weight) propylene glycol/glycerol. Corresponding activity coefficient values ζ were calculated by eq 2 using $p_{\mathrm{L}}^{\mathrm{o}}$ at 20 °C and $\overline{\text{MW}}=83.3\mathrm{g}∕\text{mol}$. Values of $p_{\mathrm{L}}^{\mathrm{o}}$ at 20 and 37 °C were used to obtain K_p values extrapolated to 37 °C by eq 9.

^bN = 3 unless NA (not available)is given for the standard deviation for the measured log K_p at 20 °C, in which case N = 1.

^cAntoine eq as given at https://webbook.nist.gov (accessed June 29, 2018).

^dAntoine eq from Diaz et al.⁶

^eAntoine eq as given in Towler and Sinnott.⁷

^f$p_{\mathrm{L}}^{\mathrm{o}}$ at 25 °C from http://www.thegoodscentscompany.com corrected to 20 °C using ΔH_vap for other butyrates.

^gAntoine eq for $p_{\mathrm{L}}^{\mathrm{o}}$ as given in Soni et al.⁸

^hAntoine eq for $p_{\mathrm{L}}^{\mathrm{o}}$ as given in Petitjeanet al.⁹

ⁱ$p_{\mathrm{L}}^{\mathrm{o}}$ at 25 °C from http://www.thegoodscentscompany.com (accessed June 29, 2018). $p_{\mathrm{L}}^{\mathrm{o}}$ at 20 °C calculated using ΔH_vap from https://www.chemeo.com/cid/10-581-5/Aromadendrene.pdf (accessed June 29, 2018).

^j$p_{\mathrm{L}}^{\mathrm{o}}$ at 25 °C from http://www.thegoodscentscompany.com (accessed June 29, 2018). $p_{\mathrm{L}}^{\mathrm{o}}$ at 20 °C calculated using ΔH_vap from https://webbook.nist.gov (accessed June 29, 2018).

^k$p_{\mathrm{L}}^{\mathrm{o}}$ at 25 °C from http://www.thegoodscentscompany.com/, accessed June 29, 2018. $p_{\mathrm{L}}^{\mathrm{o}}$ at 20 °C calculated using ΔH_vap from https://www.chemeo.com/cid/18-655-5/3-Hexen-1-ol,%20(Z)-.pdf, accessed June 29, 2018.

^l$p_{\mathrm{L}}^{\mathrm{o}}$ at 25 °C from Pubchem, Open Chemistry Database, https://pubchem.ncbi.nlm.nih.gov/, accessed June 29, 2018. $p_{\mathrm{L}}^{\mathrm{o}}$ calculated using eq 8 with ΔH_fus (kJ/mol) as follows: 2-Acetylpyrrole, 14.08; coumarin, 19.14 kJ/mol; vanillin, 22.40 kJ/mol; ethyl vanillin, 23.10 kJ/mol, all from https://webbook.nist.gov, accessed June 29, 2018. Experimental ΔH_fus values were not found for maltol and ethyl maltol, so ΔH_fus = 19.68 kJ/mol was used for both.

^mPankow.¹⁰