Compound characterization data — Eriguchi et al., 2026

Yoichiro Eriguchi, Masayuki Munemoto, Yuichiro Tokoro, Shin-ichi Yamamoto, Kosuke Sato, Shinsuke Inagi, Toshio Koizumi. “Base-free palladium-catalyzed synthesis of 2-alkoxy-1,3-dienes from primary propargyl carbonates with benzyl alcohols.” ChemRxiv (2026). https://doi.org/10.26434/chemrxiv.15007789/v1

But-2-yn-1-yl methyl carbonate
Identifier	1a
¹H NMR (400 MHz, CDCl₃)	δ 4.70 (q, J = 2.4 Hz, 2H), 3.81 (s, 3H), 1.86 (t, J = 2.4 Hz, 3H)
¹³C NMR (100.61 MHz, CDCl₃)	δ 155.38, 84.06, 72.63, 56.22, 55.02, 3.65
GC–MS	m/z [M]⁺˙: 128.05

But-3-yn-2-yl methyl carbonate
Identifier	1b
¹H NMR (400 MHz, CDCl₃)	δ 5.33–5.28 (m, 1H), 3.81 (s, 3H), 2.51 (d, J = 2.1 Hz) 1.56 (d, J = 6.7 Hz, 3H)
¹³C NMR (100.61 MHz, CDCl₃)	δ 154.82, 81.41, 73.77, 64.01, 54.95, 21.23
GC–MS	m/z [M]⁺˙: 128.05

But-2-yn-1-yl tert-butyl carbonate
Identifier	1c
¹H NMR (400 MHz, CDCl₃)	δ4.63 (q, J = 2.4 Hz, 2H), 2.96 (t, J = 2.4 Hz, 3H), 1.49 (s, 9H)
¹³C NMR (100.61 MHz, CDCl₃)	δ 153.00, 83.60, 82.65, 72.93, 55.21, 27.76, 3.64
GC–MS	m/z [M]⁺˙: 170.09

1-Bromo-4-((buta-1,3-dien-2-yloxy)methyl)benzene
Identifier	3a
¹H NMR (400 MHz, CDCl₃)	δ 7.49 (d, J = 8.4 Hz, 2H), 7.27 (d, J = 8.4 Hz, 2H), 6.23–6.16 (dd, J = 17.2, 10.8 Hz, 1H), 5.67–5.62 (dd, J = 17.2, 1.5 Hz, 1H), 5.13 (d, J = 10.8 Hz, 1H), 4.81 (s, 2H), 4.23 (s, 2H)
¹³C NMR (100.61 MHz, CDCl₃)	δ 157.89, 136.20, 133.03, 131.58, 128.88, 121.61, 114.65, 88.05, 68.46
GC–MS	m/z [M]⁺˙: 238.0
TLC Rf (hexane/dichloromethane = 9/1)	0.58
¹H NMR, decomposition-product identification (various solvents, visible-light and temperature conditions)	Decomposition occurred exclusively when using chlorinated solvents, regardless of temperature and light conditions; the decomposed products were identified as 1a and methyl vinyl ketone

((Buta-1,3-dien-2-yloxy)methyl)benzene
Identifier	3b
¹H NMR (400 MHz, CDCl₃)	δ 7.41–7.29 (m, 5H), 6.24–6.17 (dd, J = 17.2, 10.8 Hz, 1H), 5.70–5.65 (dd, J = 17.2, 1.1 Hz, 1H), 5.12 (d, J = 10.8 Hz, 1H), 4.87 (s, 2H), 4.26 (s, 1H), 4.22 (d, 1H)
¹³C NMR (100.61 MHz, CDCl₃)	δ158.11, 137.22, 133.19, 128.44, 127.72, 127.25, 114.57, 87.84, 69.22
GC–MS	m/z [M]⁺˙: 160.1
TLC Rf (hexane/dichloromethane = 9/1)	0.55

1-((Buta-1,3-dien-2-yloxy)methyl)-4-methylbenzene
Identifier	3c
¹H NMR (400 MHz, CD₂Cl₂)	δ 7.28 (d, J = 7.9 Hz, 2H), 7.19 (d, J = 7.9 Hz, 2H), 6.25–6.17 (dd, J = 17.2, 10.8 Hz, 1H), 5.63–5.58 (dd, J = 17.2, 1.6 Hz, 1H), 5.11 (d, J = 10.8 Hz, 1H), 4.81 (s, 2H), 4.27 (s, 1H), 4.22 (d, J = 1.8 Hz, 1H), 2.35 (s, 3H)
¹³C NMR (100.61 MHz, CD₂Cl₂)	δ 158.56, 138.02, 134.62, 133.72, 129.46, 127.84, 114.52, 88.00, 69.59, 21.28
GC–MS	m/z [M]⁺˙: 174.1
TLC Rf (hexane/dichloromethane = 9/1)	0.55

1-((Buta-1,3-dien-2-yloxy)methyl)-4-methoxybenzene
Identifier	3d
¹H NMR (400 MHz, CDCl₃)	δ 7.32 (d, J = 8.6 Hz, 2H), 6.90 (d, J = 8.6 Hz, 2H), 6.23–6.16 (dd, J = 17.2, 11.1 Hz, 1H), 5.66–5.61 (dd, J = 17.2, 1.4 Hz, 1H), 5.12 (d, J = 10.8 Hz, 1H), 4.79 (s, 2H), 4.26 (s, 1H), 4.22 (d, J = 1.6 Hz, 1H), 3.82 (s, 3H)
¹³C NMR (100.61 MHz, CDCl₃)	δ 159.29, 158.19, 133.26, 129.29, 128.96, 114.51, 113.86, 87.67, 69.03
GC–MS	m/z [M]⁺˙: 190.1
TLC Rf (hexane/dichloromethane = 9/1)	0.23

1-((Buta-1,3-dien-2-yloxy)methyl)-4-fluorobenzene
Identifier	3e
¹H NMR (400 MHz, CD₂Cl₂)	δ 7.41–7.37 (m, 2H), 7.10–7.06 (m, 2H), 6.25–6.18 (dd, J = 17.2, 10.8 Hz, 1H), 5.63–5.59 (dd, J = 17.2, 1.5 Hz, 1H), 5.14 (d, J = 10.8 Hz, 1H), 4.82 (s, 2H), 4.28 (s, 1H), 4.24 (d, J = 2.0 Hz, 1H)
¹⁹F NMR (376 MHz, CD₂Cl₂)	δ −115.44, −115.46, −115.47, −115.48, −115.49, −115.50, −115.52
¹³C NMR (100.61 MHz, CD₂Cl₂)	δ 164.01, 161.57, 158.43, 133.58, 129.62, 129.54, 115.71, 115.49, 114.62, 88.17, 68.96
GC–MS	m/z [M]⁺˙: 170.1
TLC Rf (hexane/dichloromethane = 9/1)	0.55

1-((Buta-1,3-dien-2-yloxy)methyl)-4-chlorobenzene
Identifier	3f
¹H NMR (400 MHz, CDCl₃)	δ 7.35–7.30 (m, 4H), 6.23–6.16 (dd, J = 17.2, 10.8 Hz, 1H), 5.67–5.62 (dd, J = 17.2, 1.5 Hz, 1H), 5.13 (d, J = 10.8 Hz, 1H), 4.82 (s, 2H), 4.23 (s, 2H)
¹³C NMR (100.61 MHz, CDCl₃)	δ 157.88, 135.66, 133.49, 133.04, 128.62, 128.56, 114.64, 88.04, 68.42
GC–MS	m/z [M]⁺˙: 194.1
TLC Rf (hexane/dichloromethane = 9/1)	0.48

1-((Buta-1,3-dien-2-yloxy)methyl)-4-(trifluoromethyl)benzene
Identifier	3g
¹H NMR (400 MHz, CD₂Cl₂)	δ 7.66 (d, J = 8.1 Hz, 2H), 7.55 (d, J = 8.1 Hz, 2H), 6.29–6.22 (dd, J = 17.2, 10.8 Hz, 1H), 5.71–5.66 (dd, J = 17.2, 1.0 Hz, 1H), 5.17 (d, J = 10.8 Hz, 1H), 4.94 (s, 2H), 4.28 (s, 2H)
¹⁹F NMR (376 MHz, CD₂Cl₂)	δ −62.80
¹³C NMR (100.61 MHz, CD₂Cl₂)	δ 158.34, 142.04, 133.48, 130.59, 130.27, 129.95, 129.63, 128.83, 127.72, 126.13, 125.84, 125.81, 125.77, 125.73, 123.42, 120.72, 114.83, 88.50, 68.81
GC–MS	m/z [M]⁺˙: 228.1
TLC Rf (hexane/dichloromethane = 9/1)	0.66

1-Bromo-3-((buta-1,3-dien-2-yloxy)methyl)benzene
Identifier	3h
¹H NMR (400 MHz, CD₂Cl₂)	δ 7.56 (s, 1H), 7.46 (d, J = 7.9 Hz, 1H), 7.34 (d, J = 7.6 Hz, 1H), 7.27 (t, J = 7.7 Hz, 1H), 6.26–6.19 (dd, J = 17.2, 10.8 Hz, 1H), 5.64 (d, J = 17.2 Hz, 1H), 5.14 (d, J = 10.8 Hz, 1H), 4.82 (s, 2H), 4.28 (s, 1H), 4.25 (d, J = 3.4 Hz, 1H)
¹³C NMR (100.61 MHz, CD₂Cl₂)	δ 158.32, 140.15, 133.45, 131.15, 130.54, 130.50, 126.22, 122.80, 114.77, 88.36, 68.75
GC–MS	m/z [M]⁺˙: 238.0
TLC Rf (hexane/dichloromethane = 9/1)	0.55

1-Bromo-2-((buta-1,3-dien-2-yloxy)methyl)benzene
Identifier	3i
¹H NMR (400 MHz, CD₂Cl₂)	δ 7.60–7.53 (m, 2H), 7.36 (t, J = 7.6 Hz, 1H), 7.22–7.18 (m, 1H), 6.28–6.21 (dd, J = 17.2, 10.8 Hz, 1H),5.71–5.67 (dd, J = 17.2, 1.5 Hz, 1H), 5.17 (d, J = 10.8 Hz, 1H), 4.93 (s, 2H), 4.31 (s, 1H), 4.29 (d, J = 2.1 Hz, 1H)
¹³C NMR (100.61 MHz, CD₂Cl₂)	δ 158.15, 136.90, 133.46, 132.92, 129.55, 129.15, 127.92, 122.65, 114.75, 88.50, 69.04
GC–MS	m/z [M]⁺˙: 238.0
TLC Rf (hexane/dichloromethane = 9/1)	0.58

(±)-Dimethyl-4-((4-bromobenzyl)oxy)cyclohex-4-ene-1,2-dicarboxylate
Identifier	(±)-4a
¹H NMR (400 MHz, CDCl₃)	δ 7.48 (d, J = 8.4 Hz, 2H), 7.21 (d, J = 8.4 Hz, 2H), 4.67 (s, 3H), 3.72–3.70 (m, 6H), 3.05–2.98 (m, 1H), 2.87–2.81 (m, 1H), 2.52–2.43 (m, 2H), 2.39–2.26 (m, 2H)
¹³C NMR (100.61 MHz, CDCl₃)	δ 1.74.94, 174.47, 152.11, 136.11, 131.58, 129.00, 121.68, 92.69, 68.12, 52.04, 51.97, 41.51, 41.43, 29.87, 26.09
GC–MS	m/z [M]⁺˙: 383.2
TLC Rf (hexane/ethyl acetate = 6/1)	0.39

Compounds 1a–1c, 3a–3i and (±)-4a
¹H and ¹³C NMR spectra	Image data were not transcribed
¹⁹F NMR spectra of 3e and 3g	Image data were not transcribed