VIENNA, Aug 27 (Reuters) - A Vienna court on Friday found disgraced former far-right leader Heinz-Christian Strache guilty of corruption and sentenced him to 15 months in jail in a case involving party donations from the owner of a private clinic. At issue was whether a quid pro quo was involved in two donations to the far-right Freedom Party (FPO) of 2,000 euros ($2,350) and 10,000 euros by Walter Grubmueller, the owner of a Vienna private clinic and a friend of Strache"s. The donations were made in 2016 and 2017, before the FPO entered government in a coalition with Chancellor Sebastian Kurz"s conservatives in December 2017. In 2018, a legislative change added the clinic to the list of facilities able to charge Austrian social security directly for some procedures, a significant extra source of income. "A factual connection has clearly been established and this was in exchange for a wealthy friend"s donation," Austrian media quoted Judge Claudia Moravec-Loidolt of the Vienna Regional Criminal Court as ruling. A lawyer for Strache said he would appeal, news agency APA reported. Grubmueller, who was also sentenced to a year in prison, plans to challenge the ruling, it added. The conviction comes two years after Strache resigned as FPO leader and Austrian vice chancellor over a video sting that showed him at a dinner party in Ibiza making various allegations about corruption in Austrian politics. Strache has said it was "a drunken affair" and he had not been speaking seriously. He has denied wrongdoing. The sting brought down the coalition between the FPO and Kurz"s conservatives. Kurz now governs with the Greens. Strache"s political career was already in tatters. He was expelled from the FPO and failed to secure a seat on Vienna"s city council last year when the rival party won just 3% of the votes.