Sun in the eleventh house is in the house of his friend Jupiter. Eleventh house rules regular income, social circle, friends and monetary gains. Sun is essentially a dazzler or one who is bright and cheerful. Naturally native with Sun in eleventh house likes to be the center of attention. If Sun in strong then native is indeed the bright spark in the friends and extended social circle. 

     According to B. V. Raman: "Natives with Sun in the eleventh house lives a long life and become wealthy. He/She would get royal and government favors and achieves success without much efforts. He/She would be wise, possess a keen intellect and also have high morals and principles in life". Sun  is essentially a malefic planet. Rule for malefic is: Great where it is placed, Bad for places where it aspects. So Sun does good for matters related to the eleventh house especially matters of regular income, social connection, career growth, promotions and gains as well as elder brothers.

     But the fifth house aspect may impact negatively on child birth, losses via stock markets or gambling as well as possibility of getting negative fame may increase. There is a possibility that native is involved in humanitarian efforts. Sun promotes confidence and positive outlook and elevent house placement could result in financial gains via confident personality. It is great in places like marketing, management, MNC's, government jobs and anyplace where a hierarchy is present. On the downside if Sun is associated or aspected by malefics or placed in an enemy sign than troubles are expected especially in matters of regular Income, relations with friends, social circle as well as for monetary gains. 

     Generally speaking this is a great position for Sun but just in case it is weak via affliction or placement in bad sign it would be wise to keep a low profile in the friends and extended social circle. Having a humanitarian and philantrophist approach would also help lessen adverse effects if any. Last but not least prayers to Lord Vishnu or Brihaspati who is the guru of devas may also help. 

References:

Raman, Bangalore Venkata. How to Judge a Horoscope. Delhi: Motilal Banarsidass, 2014. Print.