(taxpayer had recognizable gain on sale of partnership interest in exchange for stock; constructive receipt doctrine applied - taxpayer had argued that because stock subject to significant restrictions (taxpayer couldn't sell the stock for 5 years) and stock would be forfeited if taxpayer went into competition with buyer of partnership interests, or quit working for the buyer or was fired for cause or poor performance, that taxpayer did not have gain recognition; court determined that constructive receipt doctrine applied because taxpayer would benefit from appreciation in value during 5-year period, would receive dividends during five-year period and could direct the voting of shares; transaction also structured to result in full taxation in year of sale).