Table 2.

Formate coupling catalyzed by hydroxides at reaction temperatures and catalyst loadings at which the highest yields were obtained.[ ³⁴ , ²⁷³ ]

Formate	Hydroxide	T [°C]	Catalyst loading [mol equiv.]	Oxalate yield [%]
HCOONa	KOH	341	0.032	94
HCOONa	NaOH	330	0.050	92
HCOONa	NaOH	390	0.042	86
HCOONa	KOH	420	0.061	78
HCOONa	KOH	440	0.097	77
HCOOK	KOH	410	0.111	75
HCOOK	NaOH	411	0.135	70
HCOONa	KOH	341	0.032	94