* Sika CEO Jenisch to lead LafargeHolcim from mid-October
* LafargeHolcim shares jump 7 pct, Sika falls 2.5 pct
* LafargeHolcim had sought new CEO after Syrian scandal (Recasts, adding share prices, analysts)
By John Revill and John Miller
ZURICH, May 22 (Reuters) - LafargeHolcim named the boss of high-flying Swiss construction chemicals firm Sika as its new CEO on Monday, bringing a speedy end to the cement maker's search for a leader in the wake of a scandal over payments to armed groups in Syria.
The Franco-Swiss group's stock jumped 7 percent in early trading, its biggest daily increase in more than three years, following news Jan Jenisch will take over as CEO on Oct. 16.
"This is a very positive outcome for LafargeHolcim," said Bernstein analyst Phil Roseberg, highlighting Jenisch's success at Sika over the last five years.
"Jenisch has a strong track record from Sika, having made dramatic improvements to growth and profitability and outperformed the (Swiss blue-chip) SMI index by over 200 percent."
Jenisch, a 50-year-old German, takes over after LafargeHolcim has been rocked by revelations it paid protection money to keep one of its Syrian factories operating in the devastated country.
The scandal triggered the departure of Eric Olsen, a former Lafarge executive who has led the group since it was created by the merger of Switzerland's Holcim and France's Lafarge in 2015. Olsen has denied knowledge or involvement in the affair.
LafargeHolcim dismissed speculation Jenisch's appointment was designed to strengthen the Swiss side of the business at the expense of former Lafarge officials.
"The reason that Jens Jenisch was chosen was because of his successful track record at a global company, his familiarity with the building materials sector and the tremendous success Sika has had in recent years," spokesman Beat Werder said.
"We believe he is the right man to take our company to the next level ... it has nothing to do with Swiss or French control of the company."
Jenisch's departure is a blow for Sika, where he has been CEO since January 2012 and he has led resistance to a takeover attempt by France's Saint-Gobain.
Sika shares fell 2.5 percent after the announcement.
Jenisch will be replaced as CEO of Sika by Paul Schuler, Sika's regional manager for Europe, the Middle East and Africa. Schuler, a 29-year Sika veteran, has led two of the company's four business regions.
"We see the departure of Jan Jenisch as quite a loss for Sika, but appreciate that the successor was immediately announced," said Bernd Pomrehn, an analyst at Bank Vontobel. (Editing by Michael Shields and Mark Potter)