He worked from 1788 to 1804 as a silversmith in Hartford CT with a shop "a few rods north of the State House and directly opposite Mr. Joseph Pratt's tavern." 4
Advertised in the Connecticut Courant, 27 Oct 1788, noting that he sold and repaired watches and offered ". . . Chime Clocks and common eight day and thirty hour Clocks, Surveyor's Compasses, Cans, Pepper Casters, Cream Jugs, Sugar Tongs, Spoons, Buckles and all kinds of Gold Smith's and Jewelry work."
Advertised in the Hartford City Directory (Hartford CT), 1799, as a Watchmaker and jeweller, north east of the State House
Watch manufactory, a few rods south of Dr. Isaac Bull's.
He was a partner from 1799 to 1800 with Abel Buell in New Haven CT as BUEL & GREENLEAF. 3
He was a partner from 1804 to 1807 with Frederick Oakes in Hartford CT as GREENLEAF & OAKES. Partnership announced in the American Mercury of 20 December 1804 and its dissolution in the Connecticut Courant of 30 September 1807. The mark show is tentatively attributed to the firm. 4
Appointed from 1806 to 1820 as Member of Hartford Council in Hartford CT 3
He worked from 1807 to 1811 as a silversmith in Hartford CT 4
He worked after 1811 as a dentist and real estate agent in Hartford CT 3
David married Anna Jones on 15 Nov 1787 in Hartford CT. (Anna Jones was born on 7 Nov 1765 in Norwalk CT and died on 18 Oct 1828 in Hartford CT.)