Table 1.

Selected physical data of 4‐MeTHP, THP, CPME, 2‐MeTHF and THF.

Solvent property	4‐MeTHP	THP	CPME	2‐MeTHF	THF
Boiling point [°C]	105[a]	88[a]	106[a]	80[a]	65[a]
Melting point [°C]	−92[c]	−45[g]	<−140[b]	−136[b]	−108.5[b]
Density [g cm−3]	0.857[c]	0.88[g]	0.86[b]	0.85[b]	0.89[b]
Solubility in water [g/100 g, 23 °C]	1.5[a]	8[a]	1.1[a]	14[a]	miscible[a]
Dielectric constant [25 °C]	4.8[c]	5.7[a]	4.8[a]	7.0[a]	7.6[a]
Dipole moment [D]	1.86 (calcd)[c]	1.63[f]	1.27 (calcd)[b]	1.38[e]	1.7[b]
Log Pow	1.9[c]	unknown	1.59[b]	0.77[d]	0.47[b]
Flash point [°C]	6.5[c]	−16[g]	−1[b]	−11[b]	−14.5[b]

[a] Patent;19 [b] Ref. 11; [c] Published data;23 [d] Ref. 15; [e] Ref. 8; [f] Symposium abstract;26 [g] Safety data sheet (Sigma–Aldrich).27