In a large bowl, toss the shrimp with ½ teaspoon salt. In a 12-inch skillet over medium-high, heat 3 tablespoons oil until shimmering. Add half of the shrimp in a single layer and cook without stirring until browned on the bottoms but not yet fully cooked, about 2 minutes. Using tongs or a slotted spoon, transfer to a large plate. Cook the remaining shrimp in the same way using the oil remaining in the pan. Transfer to the plate.
In the same skillet over medium, combine the remaining 1 tablespoon oil and the garlic. Cook, stirring occasionally, until the garlic is fragrant and lightly browned, about 2 minutes. Add the wine and bring to a simmer over medium-high, scraping up any browned bits. Stir in the tomatoes with juices, pepper flakes, oregano and ¾ teaspoon salt. Reduce to medium and simmer, uncovered and stirring occasionally, until the sauce thickens slightly, 15 to 20 minutes. Add the butter and stir until melted.
Add the shrimp and any accumulated juices. Cook, stirring often, until the shrimp are opaque throughout, about 2 minutes. Off heat, stir in the parsley, then taste and season with salt and black pepper.
