Nature Communications

Table 1 Optimization of the reaction conditions^a

From: Palladium-catalyzed regiodivergent hydrochlorocarbonylation of alkenes for formation of acid chlorides


Entry	[Pd]	Ligand	[HCl]	Solvent	Yield (%) 2a + 3a	Ratio of 2a/3a
1	Pd(PPh₃)₂Cl₂	–	HCl	DCE	15%	76:24
2	Pd(PPh₃)₂Cl₂	–	CH₃COCl + EtOH	DCE	3%	ND
3	Pd(PPh₃)₂Cl₂	–	TMSCl+EtOH	DCE	5%	ND
4	Pd(PPh₃)₂Cl₂	–	Ph₃SiCl + EtOH	DCE	17%	75:25
5	Pd(PPh₃)₂Cl₂	–	Ph₂^tBuSiCl + EtOH	DCE	22%	73:27
6	Pd(PPh₃)₂Cl₂	–	Ph₂^tBuSiCl + AcOH	DCE	39%	73:27
7	PdCl₂	P(2-MeOPh)₃	Ph₂^tBuSiCl + AcOH	DCE	34%	88:12
8	PdCl₂	PAd₂ⁿBu	Ph₂^tBuSiCl + AcOH	DCE	30%	>99:1
9	PdCl₂	P^tBuPh₂	Ph₂^tBuSiCl + AcOH	DCE	56%	90:10
10	PdCl₂	P^tBu₃	Ph₂^tBuSiCl + AcOH	DCE	90%	97:3
11	Pd(P^tBu₃)₂	–	Ph₂^tBuSiCl + AcOH	DCE	96%	>99:1
12	PdCl₂	Dtbpx	Ph₂^tBuSiCl + AcOH	DCE	NR	ND
13	PdCl₂	DPE-Phos	Ph₂^tBuSiCl + AcOH	DCE	73%	33:67
14	PdCl₂	Xantphos	Ph₂^tBuSiCl + AcOH	DCE	67%	28:72
15	PdCl₂	^tBu-Xantphos	Ph₂^tBuSiCl + AcOH	DCE	42%	49:51
16	PdCl₂	Xantphos	Ph₂^tBuSiCl + AcOH	THF	86%	37:63
17	PdCl₂	Xantphos	Ph₂^tBuSiCl + AcOH	Toluene	75%	10:90
18	PdCl₂	Xantphos	Ph₂^tBuSiCl + AcOH	PhCl	64%	4:96
19^b	PdCl₂	Xantphos	Ph₂^tBuSiCl + AcOH	PhCl	95%	5:95

^tBu tertiary-butyl, ⁿBu normal-butyl.
^aConditions: styrene 1a (0.2 mmol), [Pd] (5 mol%), bisphosphine ligand (6 mol%) or monophosphine ligand (10 mol%), [SiCl] (0.3 mmol), EtOH or AcOH (0.3 mmol), solvent (1.5 mL), CO (30 atm), 80 °C for 24 h. The yields of 2a + 3a and ratio of regioisomers 2a/3a were determined by GC-MS analysis of their derivatized methyl carboxylate using n-hexadecane as the internal standard (see SI).
^bCO (40 atm), 100 °C for 24 h.

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