Preheat the oven to 250°C (approximately 485°F). Wipe the raspberries and mix with the lemon juice, lemon zest, raspberry liqueur, and vanilla seeds.
Add the sugar, and divide everything into the prepared jars.
Close the jars, and place in a roasting pan. Pour boiling water into the pan and cook for 20 minutes in the oven. Remove and let cool.